diff --git a/api/src/main/java/io/github/wulkanowy/api/Client.java b/api/src/main/java/io/github/wulkanowy/api/Client.java
index f7a663ec..16b7982c 100644
--- a/api/src/main/java/io/github/wulkanowy/api/Client.java
+++ b/api/src/main/java/io/github/wulkanowy/api/Client.java
@@ -5,44 +5,102 @@ import org.jsoup.Jsoup;
 import org.jsoup.nodes.Document;
 
 import java.io.IOException;
+import java.util.Date;
 import java.util.Map;
+import java.util.concurrent.TimeUnit;
+
+import io.github.wulkanowy.api.login.Login;
 
 public class Client {
 
-    private String protocol;
+    private String protocol = "https";
 
-    private String host;
+    private String host = "vulcan.net.pl";
 
-    private String symbol;
+    private String email;
+
+    private String password;
+
+    private String symbol = "Default";
+
+    private Login login;
+
+    private Date lastSuccessRequest = new Date();
 
     private Cookies cookies = new Cookies();
 
-    Client(String protocol, String host, String symbol) {
-        this.protocol = protocol;
-        this.host = host;
+    Client(String email, String password, String symbol) {
+        this.email = email;
+        this.password = password;
         this.symbol = symbol;
+
+        setFullEndpointInfo(email);
     }
 
-    String getHost() {
-        return host;
+    private void setFullEndpointInfo(String info) {
+        String[] creds = info.split("\\\\");
+
+        email = info;
+
+        if (creds.length > 2) {
+            String[] url = creds[0].split("://");
+
+            protocol = url[0];
+            host = url[1];
+            email = creds[2];
+        }
+    }
+
+    private void login() throws IOException, VulcanException {
+        if (isLoggedIn()) {
+            return;
+        }
+
+        this.symbol = getLogin().login(email, password, symbol);
+    }
+
+    private boolean isLoggedIn() {
+        return getCookies().size() > 0 &&
+                29 > TimeUnit.MILLISECONDS.toMinutes(new Date().getTime() - lastSuccessRequest.getTime());
+
+    }
+
+    Login getLogin() {
+        if (null != login) {
+            return login;
+        }
+
+        login = new Login(this);
+
+        return login;
+    }
+
+    public String getSymbol() {
+        return symbol;
     }
 
     public void setSymbol(String symbol) {
         this.symbol = symbol;
     }
 
-    Map<String, String> getCookies() {
+    private Map<String, String> getCookies() {
         return cookies.getItems();
     }
 
-    private String getFilledUrl(String url) {
+    String getHost() {
+        return host;
+    }
+
+    String getFilledUrl(String url) {
         return url
                 .replace("{schema}", protocol)
                 .replace("{host}", host.replace(":", "%253A"))
-                .replace("{symbol}", symbol == null ? "Default" : symbol);
+                .replace("{symbol}", symbol);
     }
 
-    Document getPageByUrl(String url) throws IOException {
+    Document getPageByUrl(String url) throws IOException, VulcanException {
+        login();
+
         Connection.Response response = Jsoup.connect(getFilledUrl(url))
                 .followRedirects(true)
                 .cookies(getCookies())
@@ -50,10 +108,10 @@ public class Client {
 
         this.cookies.addItems(response.cookies());
 
-        return response.parse();
+        return checkForErrors(response.parse());
     }
 
-    public Document postPageByUrl(String url, String[][] params) throws IOException {
+    public Document postPageByUrl(String url, String[][] params) throws IOException, VulcanException {
         Connection connection = Jsoup.connect(getFilledUrl(url));
 
         for (String[] data : params) {
@@ -68,10 +126,12 @@ public class Client {
 
         this.cookies.addItems(response.cookies());
 
-        return response.parse();
+        return checkForErrors(response.parse());
     }
 
-    public String getJsonStringByUrl(String url) throws IOException {
+    public String getJsonStringByUrl(String url) throws IOException, VulcanException {
+        login();
+
         Connection.Response response = Jsoup.connect(getFilledUrl(url))
                 .followRedirects(true)
                 .ignoreContentType(true)
@@ -83,7 +143,9 @@ public class Client {
         return response.body();
     }
 
-    public String postJsonStringByUrl(String url, String[][] params) throws IOException {
+    public String postJsonStringByUrl(String url, String[][] params) throws IOException, VulcanException {
+        login();
+
         Connection connection = Jsoup.connect(getFilledUrl(url));
 
         for (String[] data : params) {
@@ -101,4 +163,18 @@ public class Client {
 
         return response.body();
     }
+
+    Document checkForErrors(Document doc) throws VulcanException {
+        if ("Przerwa techniczna".equals(doc.select("title").text())) {
+            throw new VulcanOfflineException();
+        }
+
+        if ("Zaloguj się".equals(doc.select(".loginButton").text())) {
+            throw new NotLoggedInErrorException();
+        }
+
+        lastSuccessRequest = new Date();
+
+        return doc;
+    }
 }
diff --git a/api/src/main/java/io/github/wulkanowy/api/Cookies.java b/api/src/main/java/io/github/wulkanowy/api/Cookies.java
index c97d9658..dfe4c4b5 100644
--- a/api/src/main/java/io/github/wulkanowy/api/Cookies.java
+++ b/api/src/main/java/io/github/wulkanowy/api/Cookies.java
@@ -3,21 +3,15 @@ package io.github.wulkanowy.api;
 import java.util.HashMap;
 import java.util.Map;
 
-public class Cookies {
+class Cookies {
 
     private Map<String, String> jar = new HashMap<>();
 
-    public Map<String, String> getItems() {
+    Map<String, String> getItems() {
         return jar;
     }
 
-    public Cookies setItems(Map<String, String> items) {
-        this.jar = items;
-        return this;
-    }
-
-    public Cookies addItems(Map<String, String> items) {
-        this.jar.putAll(items);
-        return this;
+    void addItems(Map<String, String> items) {
+        jar.putAll(items);
     }
 }
diff --git a/api/src/main/java/io/github/wulkanowy/api/NotLoggedInErrorException.java b/api/src/main/java/io/github/wulkanowy/api/NotLoggedInErrorException.java
new file mode 100644
index 00000000..86372266
--- /dev/null
+++ b/api/src/main/java/io/github/wulkanowy/api/NotLoggedInErrorException.java
@@ -0,0 +1,4 @@
+package io.github.wulkanowy.api;
+
+public class NotLoggedInErrorException extends VulcanException {
+}
diff --git a/api/src/main/java/io/github/wulkanowy/api/SnP.java b/api/src/main/java/io/github/wulkanowy/api/SnP.java
index 614b77b6..adbffd4b 100644
--- a/api/src/main/java/io/github/wulkanowy/api/SnP.java
+++ b/api/src/main/java/io/github/wulkanowy/api/SnP.java
@@ -6,19 +6,17 @@ import org.jsoup.nodes.Element;
 import java.io.IOException;
 import java.util.List;
 
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
-
 public interface SnP {
 
     String getId();
 
-    void storeContextCookies() throws IOException, NotLoggedInErrorException;
+    StudentAndParent storeContextCookies() throws IOException, VulcanException;
 
     String getRowDataChildValue(Element e, int index);
 
-    Document getSnPPageDocument(String url) throws IOException;
+    Document getSnPPageDocument(String url) throws IOException, VulcanException;
 
-    List<Semester> getSemesters() throws IOException;
+    List<Semester> getSemesters() throws IOException, VulcanException;
 
     List<Semester> getSemesters(Document gradesPage);
 
diff --git a/api/src/main/java/io/github/wulkanowy/api/StudentAndParent.java b/api/src/main/java/io/github/wulkanowy/api/StudentAndParent.java
index a8d61913..c014e96c 100644
--- a/api/src/main/java/io/github/wulkanowy/api/StudentAndParent.java
+++ b/api/src/main/java/io/github/wulkanowy/api/StudentAndParent.java
@@ -8,8 +8,6 @@ import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
-
 public class StudentAndParent implements SnP {
 
     private static final String START_PAGE_URL = "{schema}://uonetplus.{host}/{symbol}/Start.mvc/Index";
@@ -22,12 +20,8 @@ public class StudentAndParent implements SnP {
 
     private String id;
 
-    StudentAndParent(Client client) {
-        this.client = client;
-    }
-
     StudentAndParent(Client client, String id) {
-        this(client);
+        this.client = client;
         this.id = id;
     }
 
@@ -39,11 +33,12 @@ public class StudentAndParent implements SnP {
         return id;
     }
 
-    public void storeContextCookies() throws IOException, NotLoggedInErrorException {
+    public StudentAndParent storeContextCookies() throws IOException, VulcanException {
         client.getPageByUrl(getSnpHomePageUrl());
+        return this;
     }
 
-    String getSnpHomePageUrl() throws IOException, NotLoggedInErrorException {
+    String getSnpHomePageUrl() throws IOException, VulcanException {
         if (null != getId()) {
             return getBaseUrl();
         }
@@ -77,11 +72,11 @@ public class StudentAndParent implements SnP {
         return e.select(".daneWiersz .wartosc").get(index - 1).text();
     }
 
-    public Document getSnPPageDocument(String url) throws IOException {
+    public Document getSnPPageDocument(String url) throws IOException, VulcanException {
         return client.getPageByUrl(getBaseUrl() + url);
     }
 
-    public List<Semester> getSemesters() throws IOException {
+    public List<Semester> getSemesters() throws IOException, VulcanException {
         return getSemesters(getSnPPageDocument(GRADES_PAGE_URL));
     }
 
diff --git a/api/src/main/java/io/github/wulkanowy/api/Vulcan.java b/api/src/main/java/io/github/wulkanowy/api/Vulcan.java
index a44e868f..c16ef088 100644
--- a/api/src/main/java/io/github/wulkanowy/api/Vulcan.java
+++ b/api/src/main/java/io/github/wulkanowy/api/Vulcan.java
@@ -7,12 +7,6 @@ import io.github.wulkanowy.api.attendance.AttendanceTable;
 import io.github.wulkanowy.api.exams.ExamsWeek;
 import io.github.wulkanowy.api.grades.GradesList;
 import io.github.wulkanowy.api.grades.SubjectsList;
-import io.github.wulkanowy.api.login.AccountPermissionException;
-import io.github.wulkanowy.api.login.BadCredentialsException;
-import io.github.wulkanowy.api.login.Login;
-import io.github.wulkanowy.api.login.LoginErrorException;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
-import io.github.wulkanowy.api.login.VulcanOfflineException;
 import io.github.wulkanowy.api.messages.Messages;
 import io.github.wulkanowy.api.notes.AchievementsList;
 import io.github.wulkanowy.api.notes.NotesList;
@@ -26,171 +20,92 @@ public class Vulcan {
 
     private String id;
 
-    private String symbol;
-
     private SnP snp;
 
-    private String protocolSchema = "https";
-
-    private String logHost = "vulcan.net.pl";
-
-    private String email;
-
     private Client client;
 
-    private Login login;
-
-    public void setClient(Client client) {
-        this.client = client;
-    }
-
-    public void setLogin(Login login) {
-        this.login = login;
-    }
-
-    public void login(String email, String password, String symbol)
-            throws BadCredentialsException, AccountPermissionException,
-            LoginErrorException, IOException, VulcanOfflineException {
-
-        setFullEndpointInfo(email);
-        login = getLogin();
-
-        this.symbol = login.login(this.email, password, symbol);
-    }
-
-    public Vulcan login(String email, String password, String symbol, String id)
-            throws BadCredentialsException, AccountPermissionException,
-            LoginErrorException, IOException, VulcanOfflineException {
-        login(email, password, symbol);
+    public void setCredentials(String email, String password, String symbol, String id) {
+        client = new Client(email, password, symbol);
 
         this.id = id;
-
-        return this;
     }
 
-    String getProtocolSchema() {
-        return protocolSchema;
-    }
-
-    String getLogHost() {
-        return logHost;
-    }
-
-    public String getEmail() {
-        return email;
-    }
-
-    public String getSymbol() {
-        return symbol;
-    }
-
-    private void setFullEndpointInfo(String email) {
-        String[] creds = email.split("\\\\");
-
-        this.email = email;
-
-        if (creds.length >= 2) {
-            String[] url = creds[0].split("://");
-
-            this.protocolSchema = url[0];
-            this.logHost = url[1];
-            this.email = creds[2];
+    public Client getClient() throws NotLoggedInErrorException {
+        if (null == client) {
+            throw new NotLoggedInErrorException();
         }
-    }
-
-    protected Client getClient() {
-        if (null != client) {
-            return client;
-        }
-
-        client = new Client(getProtocolSchema(), getLogHost(), symbol);
 
         return client;
     }
 
-    protected Login getLogin() {
-        if (null != login) {
-            return login;
-        }
+    public String getSymbol() throws NotLoggedInErrorException {
+        return getClient().getSymbol();
 
-        login = new Login(getClient());
-
-        return login;
     }
 
-    public SnP getStudentAndParent() throws IOException, NotLoggedInErrorException {
-        if (0 == getClient().getCookies().size()) {
-            throw new NotLoggedInErrorException();
+    public SnP getStudentAndParent() throws IOException, VulcanException {
+        if (null != this.snp) {
+            return this.snp;
         }
 
-        if (null != snp) {
-            return snp;
-        }
+        this.snp = new StudentAndParent(getClient(), id).storeContextCookies();
 
-        snp = createSnp(getClient(), id);
-
-        snp.storeContextCookies();
-
-        return snp;
+        return this.snp;
     }
 
-    SnP createSnp(Client client, String id) {
-        if (null == id) {
-            return new StudentAndParent(client);
-        }
-
-        return new StudentAndParent(client, id);
+    public String getId() throws IOException, VulcanException {
+        return getStudentAndParent().getId();
     }
 
-    public AttendanceStatistics getAttendanceStatistics() throws IOException, NotLoggedInErrorException {
-        return new AttendanceStatistics(getStudentAndParent());
-    }
-
-    public AttendanceTable getAttendanceTable() throws IOException, NotLoggedInErrorException {
+    public AttendanceTable getAttendanceTable() throws IOException, VulcanException {
         return new AttendanceTable(getStudentAndParent());
     }
 
-    public ExamsWeek getExamsList() throws IOException, NotLoggedInErrorException {
+    public AttendanceStatistics getAttendanceStatistics() throws IOException, VulcanException {
+        return new AttendanceStatistics(getStudentAndParent());
+    }
+
+    public ExamsWeek getExamsList() throws IOException, VulcanException {
         return new ExamsWeek(getStudentAndParent());
     }
 
-    public GradesList getGradesList() throws IOException, NotLoggedInErrorException {
+    public GradesList getGradesList() throws IOException, VulcanException {
         return new GradesList(getStudentAndParent());
     }
 
-    public SubjectsList getSubjectsList() throws IOException, NotLoggedInErrorException {
+    public SubjectsList getSubjectsList() throws IOException, VulcanException {
         return new SubjectsList(getStudentAndParent());
     }
 
-    public AchievementsList getAchievementsList() throws IOException, NotLoggedInErrorException {
+    public AchievementsList getAchievementsList() throws IOException, VulcanException {
         return new AchievementsList(getStudentAndParent());
     }
 
-    public NotesList getNotesList() throws IOException, NotLoggedInErrorException {
+    public NotesList getNotesList() throws IOException, VulcanException {
         return new NotesList(getStudentAndParent());
     }
 
-    public SchoolInfo getSchoolInfo() throws IOException, NotLoggedInErrorException {
+    public SchoolInfo getSchoolInfo() throws IOException, VulcanException {
         return new SchoolInfo(getStudentAndParent());
     }
 
-    public TeachersInfo getTeachersInfo() throws IOException, NotLoggedInErrorException {
+    public TeachersInfo getTeachersInfo() throws IOException, VulcanException {
         return new TeachersInfo(getStudentAndParent());
     }
 
-    public Timetable getTimetable() throws IOException, NotLoggedInErrorException {
+    public Timetable getTimetable() throws IOException, VulcanException {
         return new Timetable(getStudentAndParent());
     }
 
-    public BasicInformation getBasicInformation() throws IOException, NotLoggedInErrorException {
+    public BasicInformation getBasicInformation() throws IOException, VulcanException {
         return new BasicInformation(getStudentAndParent());
     }
 
-    public FamilyInformation getFamilyInformation() throws IOException, NotLoggedInErrorException {
+    public FamilyInformation getFamilyInformation() throws IOException, VulcanException {
         return new FamilyInformation(getStudentAndParent());
     }
 
-    public Messages getMessages() {
+    public Messages getMessages() throws VulcanException {
         return new Messages(getClient());
     }
 }
diff --git a/api/src/main/java/io/github/wulkanowy/api/VulcanException.java b/api/src/main/java/io/github/wulkanowy/api/VulcanException.java
new file mode 100644
index 00000000..0e7ed243
--- /dev/null
+++ b/api/src/main/java/io/github/wulkanowy/api/VulcanException.java
@@ -0,0 +1,4 @@
+package io.github.wulkanowy.api;
+
+public abstract class VulcanException extends Exception {
+}
diff --git a/api/src/main/java/io/github/wulkanowy/api/VulcanOfflineException.java b/api/src/main/java/io/github/wulkanowy/api/VulcanOfflineException.java
new file mode 100644
index 00000000..497fba94
--- /dev/null
+++ b/api/src/main/java/io/github/wulkanowy/api/VulcanOfflineException.java
@@ -0,0 +1,4 @@
+package io.github.wulkanowy.api;
+
+public class VulcanOfflineException extends VulcanException {
+}
diff --git a/api/src/main/java/io/github/wulkanowy/api/attendance/AttendanceStatistics.java b/api/src/main/java/io/github/wulkanowy/api/attendance/AttendanceStatistics.java
index 023a436e..29b6a6d9 100644
--- a/api/src/main/java/io/github/wulkanowy/api/attendance/AttendanceStatistics.java
+++ b/api/src/main/java/io/github/wulkanowy/api/attendance/AttendanceStatistics.java
@@ -9,6 +9,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 import io.github.wulkanowy.api.generic.Month;
 import io.github.wulkanowy.api.generic.Subject;
 
@@ -22,15 +23,15 @@ public class AttendanceStatistics {
         this.snp = snp;
     }
 
-    public Types getTypesTable() throws IOException {
+    public Types getTypesTable() throws IOException, VulcanException {
         return getTypesTable("");
     }
 
-    public Types getTypesTable(String tick) throws IOException {
+    public Types getTypesTable(String tick) throws IOException, VulcanException {
         return getTypesTable(tick, -1);
     }
 
-    public List<Subject> getSubjectList() throws IOException {
+    public List<Subject> getSubjectList() throws IOException, VulcanException {
         Element mainContainer = snp.getSnPPageDocument(attendancePageUrl)
                 .select(".mainContainer #idPrzedmiot").first();
 
@@ -46,7 +47,7 @@ public class AttendanceStatistics {
         return subjectList;
     }
 
-    public Types getTypesTable(String tick, Integer subjectId) throws IOException {
+    public Types getTypesTable(String tick, Integer subjectId) throws IOException, VulcanException {
         Element mainContainer = snp.getSnPPageDocument((attendancePageUrl
                 + "?data={tick}&idPrzedmiot={subject}")
                 .replace("{tick}", tick)
diff --git a/api/src/main/java/io/github/wulkanowy/api/attendance/AttendanceTable.java b/api/src/main/java/io/github/wulkanowy/api/attendance/AttendanceTable.java
index 677a6de0..c45cbe6a 100644
--- a/api/src/main/java/io/github/wulkanowy/api/attendance/AttendanceTable.java
+++ b/api/src/main/java/io/github/wulkanowy/api/attendance/AttendanceTable.java
@@ -12,26 +12,28 @@ import java.util.List;
 import java.util.Locale;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 import io.github.wulkanowy.api.generic.Day;
 import io.github.wulkanowy.api.generic.Lesson;
 import io.github.wulkanowy.api.generic.Week;
 
 public class AttendanceTable {
 
-    private SnP snp;
-
     private final static String ATTENDANCE_PAGE_URL = "Frekwencja.mvc?data=";
 
+    private SnP snp;
+
     public AttendanceTable(SnP snp) {
         this.snp = snp;
     }
 
-    public Week<Day> getWeekTable() throws IOException, ParseException {
+    public Week<Day> getWeekTable() throws IOException, ParseException, VulcanException {
         return getWeekTable("");
     }
 
-    public Week<Day> getWeekTable(String tick) throws IOException, ParseException {
+    public Week<Day> getWeekTable(String tick) throws IOException, ParseException, VulcanException {
         Element table = snp.getSnPPageDocument(ATTENDANCE_PAGE_URL + tick)
+
                 .select(".mainContainer .presentData").first();
 
         Elements headerCells = table.select("thead th");
diff --git a/api/src/main/java/io/github/wulkanowy/api/exams/ExamsWeek.java b/api/src/main/java/io/github/wulkanowy/api/exams/ExamsWeek.java
index b4921b8b..3dd056d9 100644
--- a/api/src/main/java/io/github/wulkanowy/api/exams/ExamsWeek.java
+++ b/api/src/main/java/io/github/wulkanowy/api/exams/ExamsWeek.java
@@ -9,6 +9,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 import io.github.wulkanowy.api.generic.Week;
 
 public class ExamsWeek {
@@ -21,11 +22,11 @@ public class ExamsWeek {
         this.snp = snp;
     }
 
-    public Week<ExamDay> getCurrent() throws IOException {
+    public Week<ExamDay> getCurrent() throws IOException, VulcanException {
         return getWeek("", true);
     }
 
-    public Week<ExamDay> getWeek(String tick, final boolean onlyNotEmpty) throws IOException {
+    public Week<ExamDay> getWeek(String tick, final boolean onlyNotEmpty) throws IOException, VulcanException {
         Document examsPage = snp.getSnPPageDocument(EXAMS_PAGE_URL + tick);
         Elements examsDays = examsPage.select(".mainContainer > div:not(.navigation)");
 
diff --git a/api/src/main/java/io/github/wulkanowy/api/grades/GradesList.java b/api/src/main/java/io/github/wulkanowy/api/grades/GradesList.java
index 44c45c9a..ce8c0f77 100644
--- a/api/src/main/java/io/github/wulkanowy/api/grades/GradesList.java
+++ b/api/src/main/java/io/github/wulkanowy/api/grades/GradesList.java
@@ -16,6 +16,7 @@ import java.util.regex.Pattern;
 
 import io.github.wulkanowy.api.Semester;
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 
 public class GradesList {
 
@@ -33,11 +34,11 @@ public class GradesList {
         return GRADES_PAGE_URL;
     }
 
-    public List<Grade> getAll() throws IOException, ParseException {
+    public List<Grade> getAll() throws IOException, ParseException, VulcanException {
         return getAll("");
     }
 
-    public List<Grade> getAll(String semester) throws IOException, ParseException {
+    public List<Grade> getAll(String semester) throws IOException, ParseException, VulcanException {
         Document gradesPage = snp.getSnPPageDocument(getGradesPageUrl() + semester);
         Elements gradesRows = gradesPage.select(".ocenySzczegoly-table > tbody > tr");
         Semester currentSemester = snp.getCurrentSemester(snp.getSemesters(gradesPage));
diff --git a/api/src/main/java/io/github/wulkanowy/api/grades/SubjectsList.java b/api/src/main/java/io/github/wulkanowy/api/grades/SubjectsList.java
index decf4468..99359413 100644
--- a/api/src/main/java/io/github/wulkanowy/api/grades/SubjectsList.java
+++ b/api/src/main/java/io/github/wulkanowy/api/grades/SubjectsList.java
@@ -9,6 +9,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 
 public class SubjectsList {
 
@@ -20,7 +21,7 @@ public class SubjectsList {
         this.snp = snp;
     }
 
-    public List<Subject> getAll() throws IOException {
+    public List<Subject> getAll() throws IOException, VulcanException {
         Document subjectPage = snp.getSnPPageDocument(SUBJECTS_PAGE_URL);
 
         Elements rows = subjectPage.select(".ocenyZwykle-table > tbody > tr");
diff --git a/api/src/main/java/io/github/wulkanowy/api/login/AccountPermissionException.java b/api/src/main/java/io/github/wulkanowy/api/login/AccountPermissionException.java
index 15be359c..99feb86f 100644
--- a/api/src/main/java/io/github/wulkanowy/api/login/AccountPermissionException.java
+++ b/api/src/main/java/io/github/wulkanowy/api/login/AccountPermissionException.java
@@ -1,4 +1,6 @@
 package io.github.wulkanowy.api.login;
 
-public class AccountPermissionException extends Exception {
+import io.github.wulkanowy.api.VulcanException;
+
+public class AccountPermissionException extends VulcanException {
 }
diff --git a/api/src/main/java/io/github/wulkanowy/api/login/BadCredentialsException.java b/api/src/main/java/io/github/wulkanowy/api/login/BadCredentialsException.java
index 4502bb15..1ac37f9c 100644
--- a/api/src/main/java/io/github/wulkanowy/api/login/BadCredentialsException.java
+++ b/api/src/main/java/io/github/wulkanowy/api/login/BadCredentialsException.java
@@ -1,4 +1,6 @@
 package io.github.wulkanowy.api.login;
 
-public class BadCredentialsException extends Exception {
+import io.github.wulkanowy.api.VulcanException;
+
+public class BadCredentialsException extends VulcanException {
 }
diff --git a/api/src/main/java/io/github/wulkanowy/api/login/Login.java b/api/src/main/java/io/github/wulkanowy/api/login/Login.java
index e680804a..7f88037d 100644
--- a/api/src/main/java/io/github/wulkanowy/api/login/Login.java
+++ b/api/src/main/java/io/github/wulkanowy/api/login/Login.java
@@ -8,6 +8,7 @@ import org.jsoup.select.Elements;
 import java.io.IOException;
 
 import io.github.wulkanowy.api.Client;
+import io.github.wulkanowy.api.VulcanException;
 
 public class Login {
 
@@ -27,16 +28,13 @@ public class Login {
         this.client = client;
     }
 
-    public String login(String email, String password, String symbol)
-            throws BadCredentialsException, LoginErrorException,
-            AccountPermissionException, IOException, VulcanOfflineException {
+    public String login(String email, String password, String symbol) throws VulcanException, IOException {
         String certificate = sendCredentials(email, password, symbol);
 
         return sendCertificate(certificate, symbol);
     }
 
-    String sendCredentials(String email, String password, String symbol)
-            throws IOException, BadCredentialsException {
+    String sendCredentials(String email, String password, String symbol) throws IOException, VulcanException {
         this.symbol = symbol;
 
         Document html = client.postPageByUrl(LOGIN_PAGE_URL, new String[][]{
@@ -51,25 +49,20 @@ public class Login {
         return html.select("input[name=wresult]").attr("value");
     }
 
-    String sendCertificate(String certificate, String defaultSymbol)
-            throws IOException, LoginErrorException, AccountPermissionException, VulcanOfflineException {
+    String sendCertificate(String certificate, String defaultSymbol) throws IOException, VulcanException {
         this.symbol = findSymbol(defaultSymbol, certificate);
         client.setSymbol(this.symbol);
 
-        Document html = client.postPageByUrl(LOGIN_ENDPOINT_PAGE_URL, new String[][]{
+        String title = client.postPageByUrl(LOGIN_ENDPOINT_PAGE_URL, new String[][]{
                 {"wa", "wsignin1.0"},
                 {"wresult", certificate}
-        });
+        }).select("title").text();
 
-        if (html.getElementsByTag("title").text().equals("Logowanie")) {
+        if ("Logowanie".equals(title)) {
             throw new AccountPermissionException();
         }
 
-        if (html.getElementsByTag("title").text().equals("Przerwa techniczna")) {
-            throw new VulcanOfflineException();
-        }
-
-        if (!html.select("title").text().equals("Uonet+")) {
+        if (!"Uonet+".equals(title)) {
             throw new LoginErrorException();
         }
 
@@ -85,7 +78,8 @@ public class Login {
     }
 
     String findSymbolInCertificate(String certificate) {
-        Elements els = Jsoup.parse(certificate.replaceAll(":", ""), "", Parser.xmlParser())
+        Elements els = Jsoup
+                .parse(certificate.replaceAll(":", ""), "", Parser.xmlParser())
                 .select("[AttributeName=\"UserInstance\"] samlAttributeValue");
 
         if (els.isEmpty()) {
@@ -94,4 +88,4 @@ public class Login {
 
         return els.get(1).text();
     }
-}
\ No newline at end of file
+}
diff --git a/api/src/main/java/io/github/wulkanowy/api/login/LoginErrorException.java b/api/src/main/java/io/github/wulkanowy/api/login/LoginErrorException.java
index eec2b4e4..e264dc67 100644
--- a/api/src/main/java/io/github/wulkanowy/api/login/LoginErrorException.java
+++ b/api/src/main/java/io/github/wulkanowy/api/login/LoginErrorException.java
@@ -1,4 +1,6 @@
 package io.github.wulkanowy.api.login;
 
+import io.github.wulkanowy.api.NotLoggedInErrorException;
+
 public class LoginErrorException extends NotLoggedInErrorException {
 }
diff --git a/api/src/main/java/io/github/wulkanowy/api/login/NotLoggedInErrorException.java b/api/src/main/java/io/github/wulkanowy/api/login/NotLoggedInErrorException.java
deleted file mode 100644
index d33b892d..00000000
--- a/api/src/main/java/io/github/wulkanowy/api/login/NotLoggedInErrorException.java
+++ /dev/null
@@ -1,4 +0,0 @@
-package io.github.wulkanowy.api.login;
-
-public class NotLoggedInErrorException extends Exception {
-}
diff --git a/api/src/main/java/io/github/wulkanowy/api/login/VulcanOfflineException.java b/api/src/main/java/io/github/wulkanowy/api/login/VulcanOfflineException.java
deleted file mode 100644
index 45cf6458..00000000
--- a/api/src/main/java/io/github/wulkanowy/api/login/VulcanOfflineException.java
+++ /dev/null
@@ -1,4 +0,0 @@
-package io.github.wulkanowy.api.login;
-
-public class VulcanOfflineException extends Exception {
-}
diff --git a/api/src/main/java/io/github/wulkanowy/api/messages/BadRequestException.java b/api/src/main/java/io/github/wulkanowy/api/messages/BadRequestException.java
index 90af17ce..ed407b4d 100644
--- a/api/src/main/java/io/github/wulkanowy/api/messages/BadRequestException.java
+++ b/api/src/main/java/io/github/wulkanowy/api/messages/BadRequestException.java
@@ -1,4 +1,6 @@
 package io.github.wulkanowy.api.messages;
 
-class BadRequestException extends Exception {
+import io.github.wulkanowy.api.VulcanException;
+
+class BadRequestException extends VulcanException {
 }
diff --git a/api/src/main/java/io/github/wulkanowy/api/messages/Messages.java b/api/src/main/java/io/github/wulkanowy/api/messages/Messages.java
index 4eb969cd..eb5f8bba 100644
--- a/api/src/main/java/io/github/wulkanowy/api/messages/Messages.java
+++ b/api/src/main/java/io/github/wulkanowy/api/messages/Messages.java
@@ -7,7 +7,8 @@ import java.io.IOException;
 import java.util.List;
 
 import io.github.wulkanowy.api.Client;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
+import io.github.wulkanowy.api.NotLoggedInErrorException;
+import io.github.wulkanowy.api.VulcanException;
 
 public class Messages {
 
@@ -37,19 +38,19 @@ public class Messages {
         this.client = client;
     }
 
-    public List<Message> getReceived() throws IOException, NotLoggedInErrorException, BadRequestException {
+    public List<Message> getReceived() throws IOException, VulcanException {
         return getMessages(RECEIVED_URL);
     }
 
-    public List<Message> getSent() throws IOException, NotLoggedInErrorException, BadRequestException {
+    public List<Message> getSent() throws IOException, VulcanException {
         return getMessages(SENT_URL);
     }
 
-    public List<Message> getDeleted() throws IOException, NotLoggedInErrorException, BadRequestException {
+    public List<Message> getDeleted() throws IOException, VulcanException {
         return getMessages(DELETED_URL);
     }
 
-    private List<Message> getMessages(String url) throws IOException, NotLoggedInErrorException, BadRequestException {
+    private List<Message> getMessages(String url) throws IOException, VulcanException {
         String res = client.getJsonStringByUrl(url);
 
         List<Message> messages;
@@ -67,7 +68,7 @@ public class Messages {
         return messages;
     }
 
-    public Message getMessage(int id, int folder) throws IOException, BadRequestException, NotLoggedInErrorException {
+    public Message getMessage(int id, int folder) throws IOException, VulcanException {
         String res = client.postJsonStringByUrl(MESSAGE_URL, new String[][]{
                 {"idWiadomosc", String.valueOf(id)},
                 {"Folder", String.valueOf(folder)}
diff --git a/api/src/main/java/io/github/wulkanowy/api/notes/AchievementsList.java b/api/src/main/java/io/github/wulkanowy/api/notes/AchievementsList.java
index c821e8be..11d01342 100644
--- a/api/src/main/java/io/github/wulkanowy/api/notes/AchievementsList.java
+++ b/api/src/main/java/io/github/wulkanowy/api/notes/AchievementsList.java
@@ -8,6 +8,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 
 public class AchievementsList {
 
@@ -21,7 +22,7 @@ public class AchievementsList {
         this.snp = snp;
     }
 
-    public List<String> getAllAchievements() throws IOException {
+    public List<String> getAllAchievements() throws IOException, VulcanException {
         Element pageFragment = snp.getSnPPageDocument(NOTES_PAGE_URL)
                 .select(".mainContainer > div").get(1);
         Elements items = pageFragment.select("article");
diff --git a/api/src/main/java/io/github/wulkanowy/api/notes/NotesList.java b/api/src/main/java/io/github/wulkanowy/api/notes/NotesList.java
index 34b8540d..0c8a30b6 100644
--- a/api/src/main/java/io/github/wulkanowy/api/notes/NotesList.java
+++ b/api/src/main/java/io/github/wulkanowy/api/notes/NotesList.java
@@ -8,6 +8,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 
 public class NotesList {
 
@@ -21,7 +22,7 @@ public class NotesList {
         this.snp = snp;
     }
 
-    public List<Note> getAllNotes() throws IOException {
+    public List<Note> getAllNotes() throws IOException, VulcanException {
         Element pageFragment = snp.getSnPPageDocument(NOTES_PAGE_URL)
                 .select(".mainContainer > div").get(0);
         Elements items = pageFragment.select("article");
diff --git a/api/src/main/java/io/github/wulkanowy/api/school/SchoolInfo.java b/api/src/main/java/io/github/wulkanowy/api/school/SchoolInfo.java
index 4eeb641c..51a7278b 100644
--- a/api/src/main/java/io/github/wulkanowy/api/school/SchoolInfo.java
+++ b/api/src/main/java/io/github/wulkanowy/api/school/SchoolInfo.java
@@ -5,6 +5,7 @@ import org.jsoup.nodes.Element;
 import java.io.IOException;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 
 public class SchoolInfo {
 
@@ -16,7 +17,7 @@ public class SchoolInfo {
         this.snp = snp;
     }
 
-    public SchoolData getSchoolData() throws IOException {
+    public SchoolData getSchoolData() throws IOException, VulcanException {
         Element e = snp.getSnPPageDocument(SCHOOL_PAGE_URL)
                 .select(".mainContainer > article").get(0);
 
diff --git a/api/src/main/java/io/github/wulkanowy/api/school/TeachersInfo.java b/api/src/main/java/io/github/wulkanowy/api/school/TeachersInfo.java
index e8af6744..bbf5f5d7 100644
--- a/api/src/main/java/io/github/wulkanowy/api/school/TeachersInfo.java
+++ b/api/src/main/java/io/github/wulkanowy/api/school/TeachersInfo.java
@@ -9,6 +9,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 
 public class TeachersInfo {
 
@@ -20,7 +21,7 @@ public class TeachersInfo {
         this.snp = snp;
     }
 
-    public TeachersData getTeachersData() throws IOException {
+    public TeachersData getTeachersData() throws IOException, VulcanException {
         Document doc = snp.getSnPPageDocument(SCHOOL_PAGE_URL);
         Elements rows = doc.select(".mainContainer > table tbody tr");
         String description = doc.select(".mainContainer > p").first().text();
diff --git a/api/src/main/java/io/github/wulkanowy/api/timetable/Timetable.java b/api/src/main/java/io/github/wulkanowy/api/timetable/Timetable.java
index 1d526494..f575edb3 100644
--- a/api/src/main/java/io/github/wulkanowy/api/timetable/Timetable.java
+++ b/api/src/main/java/io/github/wulkanowy/api/timetable/Timetable.java
@@ -13,6 +13,7 @@ import java.util.List;
 import java.util.Locale;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 import io.github.wulkanowy.api.generic.Day;
 import io.github.wulkanowy.api.generic.Lesson;
 import io.github.wulkanowy.api.generic.Week;
@@ -27,11 +28,11 @@ public class Timetable {
         this.snp = snp;
     }
 
-    public Week<Day> getWeekTable() throws IOException, ParseException {
+    public Week<Day> getWeekTable() throws IOException, ParseException, VulcanException {
         return getWeekTable("");
     }
 
-    public Week<Day> getWeekTable(final String tick) throws IOException, ParseException {
+    public Week<Day> getWeekTable(final String tick) throws IOException, ParseException, VulcanException {
         Element table = snp.getSnPPageDocument(TIMETABLE_PAGE_URL + tick)
                 .select(".mainContainer .presentData").first();
 
diff --git a/api/src/main/java/io/github/wulkanowy/api/user/BasicInformation.java b/api/src/main/java/io/github/wulkanowy/api/user/BasicInformation.java
index 875cc8da..4edc5117 100644
--- a/api/src/main/java/io/github/wulkanowy/api/user/BasicInformation.java
+++ b/api/src/main/java/io/github/wulkanowy/api/user/BasicInformation.java
@@ -6,6 +6,7 @@ import org.jsoup.nodes.Element;
 import java.io.IOException;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 
 public class BasicInformation {
 
@@ -21,7 +22,7 @@ public class BasicInformation {
         this.snp = snp;
     }
 
-    public Document getStudentDataPageDocument() throws IOException {
+    public Document getStudentDataPageDocument() throws IOException, VulcanException {
         if (null == studentDataPageDocument) {
             studentDataPageDocument = snp.getSnPPageDocument(STUDENT_DATA_PAGE_URL);
         }
@@ -29,7 +30,7 @@ public class BasicInformation {
         return studentDataPageDocument;
     }
 
-    public PersonalData getPersonalData() throws IOException {
+    public PersonalData getPersonalData() throws IOException, VulcanException {
         Element e = getStudentDataPageDocument().select(CONTENT_QUERY).get(0);
 
         String name = snp.getRowDataChildValue(e, 1);
@@ -48,7 +49,7 @@ public class BasicInformation {
                 .setParentsNames(snp.getRowDataChildValue(e, 7));
     }
 
-    public AddressData getAddressData() throws IOException {
+    public AddressData getAddressData() throws IOException, VulcanException {
         Element e = getStudentDataPageDocument().select(CONTENT_QUERY).get(1);
 
         return new AddressData()
@@ -58,7 +59,7 @@ public class BasicInformation {
 
     }
 
-    public ContactDetails getContactDetails() throws IOException {
+    public ContactDetails getContactDetails() throws IOException, VulcanException {
         Element e = getStudentDataPageDocument().select(CONTENT_QUERY).get(2);
 
         return new ContactDetails()
diff --git a/api/src/main/java/io/github/wulkanowy/api/user/FamilyInformation.java b/api/src/main/java/io/github/wulkanowy/api/user/FamilyInformation.java
index 555de866..f5a459ee 100644
--- a/api/src/main/java/io/github/wulkanowy/api/user/FamilyInformation.java
+++ b/api/src/main/java/io/github/wulkanowy/api/user/FamilyInformation.java
@@ -8,6 +8,7 @@ import java.util.ArrayList;
 import java.util.List;
 
 import io.github.wulkanowy.api.SnP;
+import io.github.wulkanowy.api.VulcanException;
 
 public class FamilyInformation {
 
@@ -19,7 +20,7 @@ public class FamilyInformation {
         this.snp = snp;
     }
 
-    public List<FamilyMember> getFamilyMembers() throws IOException {
+    public List<FamilyMember> getFamilyMembers() throws IOException, VulcanException {
         Elements membersElements = snp.getSnPPageDocument(STUDENT_DATA_PAGE_URL)
                 .select(".mainContainer > article:nth-of-type(n+4)");
 
diff --git a/api/src/test/java/io/github/wulkanowy/api/ClientTest.java b/api/src/test/java/io/github/wulkanowy/api/ClientTest.java
new file mode 100644
index 00000000..4aa1be91
--- /dev/null
+++ b/api/src/test/java/io/github/wulkanowy/api/ClientTest.java
@@ -0,0 +1,80 @@
+package io.github.wulkanowy.api;
+
+import org.hamcrest.CoreMatchers;
+import org.jsoup.Jsoup;
+import org.jsoup.nodes.Document;
+import org.junit.Assert;
+import org.junit.Test;
+
+import io.github.wulkanowy.api.login.Login;
+
+public class ClientTest {
+
+    private String getFixtureAsString(String fixtureFileName) {
+        return FixtureHelper.getAsString(getClass().getResourceAsStream(fixtureFileName));
+    }
+
+    @Test
+    public void setFullEndpointInfoTest() throws Exception {
+        Client client = new Client("http://fakelog.net\\\\admin", "pass", "Default");
+
+        Assert.assertEquals("fakelog.net", client.getHost());
+        Assert.assertEquals("Default", client.getSymbol());
+    }
+
+    @Test
+    public void checkForNoErrorsTest() throws Exception {
+        Client client = new Client("", "", "");
+
+        Document doc = Jsoup.parse(getFixtureAsString("login/Logowanie-success.html"));
+
+        Assert.assertEquals(doc, client.checkForErrors(doc));
+    }
+
+    @Test(expected = VulcanOfflineException.class)
+    public void checkForErrorsOffline() throws Exception {
+        Client client = new Client("", "", "");
+
+        Document doc = Jsoup.parse(getFixtureAsString("login/PrzerwaTechniczna.html"));
+
+        client.checkForErrors(doc);
+    }
+
+    @Test(expected = NotLoggedInErrorException.class)
+    public void checkForErrors() throws Exception {
+        Client client = new Client("", "", "");
+
+        Document doc = Jsoup.parse(getFixtureAsString("login/Logowanie-notLoggedIn.html"));
+
+        client.checkForErrors(doc);
+    }
+
+    @Test
+    public void getClientTest() throws Exception {
+        Client client = new Client("", "", "");
+
+        Assert.assertThat(client.getLogin(), CoreMatchers.instanceOf(Login.class));
+    }
+
+    @Test
+    public void getClientTwiceTest() throws Exception {
+        Client client = new Client("", "", "");
+
+        Assert.assertEquals(client.getLogin(), client.getLogin());
+    }
+
+    @Test
+    public void getFilledUrlTest() throws Exception {
+        Client client = new Client("http://fakelog.cf\\\\admin", "", "symbol123");
+
+        Assert.assertEquals("http://uonetplus.fakelog.cf/symbol123/LoginEndpoint.aspx",
+                client.getFilledUrl("{schema}://uonetplus.{host}/{symbol}/LoginEndpoint.aspx"));
+    }
+
+    @Test
+    public void getSymbolTest() throws Exception {
+        Client client = new Client("", "", "symbol4321");
+
+        Assert.assertEquals("symbol4321", client.getSymbol());
+    }
+}
diff --git a/api/src/test/java/io/github/wulkanowy/api/StudentAndParentTest.java b/api/src/test/java/io/github/wulkanowy/api/StudentAndParentTest.java
index 89a5b190..5cde9b64 100644
--- a/api/src/test/java/io/github/wulkanowy/api/StudentAndParentTest.java
+++ b/api/src/test/java/io/github/wulkanowy/api/StudentAndParentTest.java
@@ -10,8 +10,6 @@ import org.mockito.Mockito;
 import java.util.ArrayList;
 import java.util.List;
 
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
-
 public class StudentAndParentTest {
 
     private Client client;
@@ -45,7 +43,7 @@ public class StudentAndParentTest {
 
         Mockito.when(client.getHost()).thenReturn("vulcan.net.pl");
         Mockito.when(client.getPageByUrl(Mockito.anyString())).thenReturn(startPageDocument);
-        StudentAndParent snp = new StudentAndParent(client);
+        StudentAndParent snp = new StudentAndParent(client, null);
 
         Assert.assertEquals("https://uonetplus-opiekun.vulcan.net.pl/symbol/534213/Start/Index/",
                 snp.getSnpHomePageUrl());
@@ -58,7 +56,7 @@ public class StudentAndParentTest {
         );
 
         Mockito.when(client.getPageByUrl(Mockito.anyString())).thenReturn(wrongPageDocument);
-        StudentAndParent snp = new StudentAndParent(client);
+        StudentAndParent snp = new StudentAndParent(client, null);
 
         snp.getSnpHomePageUrl();
     }
diff --git a/api/src/test/java/io/github/wulkanowy/api/VulcanTest.java b/api/src/test/java/io/github/wulkanowy/api/VulcanTest.java
index a80c798a..bda66e8d 100644
--- a/api/src/test/java/io/github/wulkanowy/api/VulcanTest.java
+++ b/api/src/test/java/io/github/wulkanowy/api/VulcanTest.java
@@ -1,86 +1,31 @@
 package io.github.wulkanowy.api;
 
+import org.hamcrest.CoreMatchers;
 import org.junit.Assert;
-import org.junit.Before;
 import org.junit.Test;
-import org.mockito.Mockito;
-
-import java.util.HashMap;
-import java.util.Map;
-
-import io.github.wulkanowy.api.login.Login;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
 
 public class VulcanTest {
 
-    private Vulcan vulcan;
+    @Test(expected = NotLoggedInErrorException.class)
+    public void getClientWithoutLoginTest() throws Exception {
+        Vulcan vulcan = new Vulcan();
 
-    @Before
-    public void setUp() throws Exception {
-        vulcan = new Vulcan();
-        vulcan.setClient(Mockito.mock(Client.class));
-        vulcan.setLogin(Mockito.mock(Login.class));
+        vulcan.getClient();
     }
 
     @Test
-    public void setFullEndpointInfoTest() throws Exception {
-        vulcan.login("http://fakelog.net\\\\admin", "pass", "Default", "123");
+    public void getClientTest() throws Exception {
+        Vulcan vulcan = new Vulcan();
+        vulcan.setCredentials("email", "password", "symbol", null);
 
-        Assert.assertEquals("http", vulcan.getProtocolSchema());
-        Assert.assertEquals("fakelog.net", vulcan.getLogHost());
-        Assert.assertEquals("admin", vulcan.getEmail());
+        Assert.assertThat(vulcan.getClient(), CoreMatchers.instanceOf(Client.class));
     }
 
     @Test
     public void getClientTwiceTest() throws Exception {
         Vulcan vulcan = new Vulcan();
-        Assert.assertTrue(vulcan.getClient().equals(vulcan.getClient()));
-    }
+        vulcan.setCredentials("email", "password", "symbol", null);
 
-    @Test
-    public void getLoginTwiceTest() throws Exception {
-        Vulcan vulcan = new Vulcan();
-        Assert.assertTrue(vulcan.getLogin().equals(vulcan.getLogin()));
-    }
-
-    @Test(expected = NotLoggedInErrorException.class)
-    public void getStudentAndParentNotLoggedInTest() throws Exception {
-        vulcan.getStudentAndParent();
-    }
-
-    @Test
-    public void getStudentAndParentTwiceTest() throws Exception {
-        Client client = Mockito.mock(Client.class);
-        Map<String, String> cookies = new HashMap<>();
-        cookies.put("test", "test");
-        Mockito.when(client.getCookies()).thenReturn(cookies);
-
-        SnP snp = Mockito.mock(StudentAndParent.class);
-        Mockito.doNothing().when(snp).storeContextCookies();
-
-        Vulcan vulcan = Mockito.mock(Vulcan.class);
-        Mockito.when(vulcan.getClient()).thenReturn(client);
-        Mockito.when(vulcan.getStudentAndParent()).thenCallRealMethod();
-        Mockito.when(vulcan.createSnp(Mockito.any(Client.class), Mockito.any())).thenReturn(snp);
-
-        vulcan.getStudentAndParent();
-        vulcan.getStudentAndParent();
-    }
-
-    @Test
-    public void createSnPTest() throws Exception {
-        vulcan.login("wulkanowy@wulkanowy.io", "wulkanowy123", "wulkan");
-
-        SnP snp1 = vulcan.createSnp(Mockito.mock(Client.class), null);
-        Assert.assertEquals(null, snp1.getId());
-
-        SnP snp2 = vulcan.createSnp(Mockito.mock(Client.class), "wulkan");
-        Assert.assertEquals("wulkan", snp2.getId());
-
-    }
-
-    @Test(expected = NotLoggedInErrorException.class)
-    public void getAttendanceExceptionText() throws Exception {
-        vulcan.getAttendanceTable();
+        Assert.assertEquals(vulcan.getClient(), vulcan.getClient());
     }
 }
diff --git a/api/src/test/java/io/github/wulkanowy/api/login/LoginTest.java b/api/src/test/java/io/github/wulkanowy/api/login/LoginTest.java
index 335ab84b..69118018 100644
--- a/api/src/test/java/io/github/wulkanowy/api/login/LoginTest.java
+++ b/api/src/test/java/io/github/wulkanowy/api/login/LoginTest.java
@@ -1,6 +1,5 @@
 package io.github.wulkanowy.api.login;
 
-
 import org.jsoup.Jsoup;
 import org.jsoup.nodes.Document;
 import org.junit.Assert;
@@ -79,13 +78,6 @@ public class LoginTest {
         login.sendCertificate(getFixtureAsString("cert.xml"), "demo123");
     }
 
-    @Test(expected = VulcanOfflineException.class)
-    public void sendCertificateVulcanOfflineTest() throws Exception {
-        Login login = new Login(getClient("PrzerwaTechniczna.html"));
-
-        login.sendCertificate(getFixtureAsString("cert.xml"), "demo123");
-    }
-
     @Test
     public void findSymbolInCertificateTest() throws Exception {
         Login login = new Login(getClient("Logowanie-certyfikat.html"));
diff --git a/api/src/test/java/io/github/wulkanowy/api/messages/MessagesTest.java b/api/src/test/java/io/github/wulkanowy/api/messages/MessagesTest.java
index 44880a88..14fa4627 100644
--- a/api/src/test/java/io/github/wulkanowy/api/messages/MessagesTest.java
+++ b/api/src/test/java/io/github/wulkanowy/api/messages/MessagesTest.java
@@ -8,7 +8,7 @@ import java.util.List;
 
 import io.github.wulkanowy.api.Client;
 import io.github.wulkanowy.api.FixtureHelper;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
+import io.github.wulkanowy.api.NotLoggedInErrorException;
 
 public class MessagesTest {
 
diff --git a/api/src/test/resources/io/github/wulkanowy/api/login/Logowanie-notLoggedIn.html b/api/src/test/resources/io/github/wulkanowy/api/login/Logowanie-notLoggedIn.html
new file mode 100644
index 00000000..f961bf82
--- /dev/null
+++ b/api/src/test/resources/io/github/wulkanowy/api/login/Logowanie-notLoggedIn.html
@@ -0,0 +1,22 @@
+<!DOCTYPE html>
+<html xmlns="http://www.w3.org/1999/xhtml">
+<head>
+    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
+    <title>Dziennik UONET+</title>
+</head>
+<body>
+<div id="MainPage_InfoPage">
+    <div class="startScreen">
+        <div class="topBar">
+            <div class="loginBox">
+                <div>
+                    <a href="/LoginEndpoint.aspx" class="loginButton"></a>
+                    <a href="/LoginEndpoint.aspx" class="loginButton">Zaloguj się</a>
+                </div>
+            </div>
+        </div>
+        <div class="bottomBar"><span>Uonet+ wersja 17.09.0007.26300</span></div>
+    </div>
+</div>
+</body>
+</html>
diff --git a/app/src/main/java/io/github/wulkanowy/data/Repository.java b/app/src/main/java/io/github/wulkanowy/data/Repository.java
index 2637b08c..d25be8b5 100644
--- a/app/src/main/java/io/github/wulkanowy/data/Repository.java
+++ b/app/src/main/java/io/github/wulkanowy/data/Repository.java
@@ -7,10 +7,7 @@ import java.util.List;
 import javax.inject.Inject;
 import javax.inject.Singleton;
 
-import io.github.wulkanowy.api.login.AccountPermissionException;
-import io.github.wulkanowy.api.login.BadCredentialsException;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
-import io.github.wulkanowy.api.login.VulcanOfflineException;
+import io.github.wulkanowy.api.VulcanException;
 import io.github.wulkanowy.data.db.dao.entities.Account;
 import io.github.wulkanowy.data.db.dao.entities.AttendanceLesson;
 import io.github.wulkanowy.data.db.dao.entities.DaoSession;
@@ -21,8 +18,8 @@ import io.github.wulkanowy.data.db.dao.entities.WeekDao;
 import io.github.wulkanowy.data.db.resources.ResourcesContract;
 import io.github.wulkanowy.data.db.shared.SharedPrefContract;
 import io.github.wulkanowy.data.sync.SyncContract;
+import io.github.wulkanowy.data.sync.account.AccountSyncContract;
 import io.github.wulkanowy.data.sync.attendance.AttendanceSyncContract;
-import io.github.wulkanowy.data.sync.login.LoginSyncContract;
 import io.github.wulkanowy.data.sync.timetable.TimetableSyncContract;
 import io.github.wulkanowy.di.annotations.SyncGrades;
 import io.github.wulkanowy.di.annotations.SyncSubjects;
@@ -37,7 +34,7 @@ public class Repository implements RepositoryContract {
 
     private final DaoSession daoSession;
 
-    private final LoginSyncContract loginSync;
+    private final AccountSyncContract accountSync;
 
     private final AttendanceSyncContract attendanceSync;
 
@@ -51,7 +48,7 @@ public class Repository implements RepositoryContract {
     Repository(SharedPrefContract sharedPref,
                ResourcesContract resources,
                DaoSession daoSession,
-               LoginSyncContract loginSync,
+               AccountSyncContract accountSync,
                AttendanceSyncContract attendanceSync,
                TimetableSyncContract timetableSync,
                @SyncGrades SyncContract gradeSync,
@@ -59,7 +56,7 @@ public class Repository implements RepositoryContract {
         this.sharedPref = sharedPref;
         this.resources = resources;
         this.daoSession = daoSession;
-        this.loginSync = loginSync;
+        this.accountSync = accountSync;
         this.attendanceSync = attendanceSync;
         this.timetableSync = timetableSync;
         this.gradeSync = gradeSync;
@@ -92,50 +89,48 @@ public class Repository implements RepositoryContract {
     }
 
     @Override
-    public void loginUser(String email, String password, String symbol)
-            throws NotLoggedInErrorException, AccountPermissionException, IOException,
-            CryptoException, VulcanOfflineException, BadCredentialsException {
-        loginSync.loginUser(email, password, symbol);
+    public void registerUser(String email, String password, String symbol) throws VulcanException,
+            IOException, CryptoException {
+        accountSync.registerUser(email, password, symbol);
     }
 
     @Override
-    public void loginCurrentUser() throws NotLoggedInErrorException, AccountPermissionException,
-            IOException, CryptoException, VulcanOfflineException, BadCredentialsException {
-        loginSync.loginCurrentUser();
+    public void initLastUser() throws VulcanException, IOException, CryptoException {
+        accountSync.initLastUser();
     }
 
     @Override
-    public void syncGrades() throws NotLoggedInErrorException, IOException, ParseException {
+    public void syncGrades() throws VulcanException, IOException, ParseException {
         gradeSync.sync();
     }
 
     @Override
-    public void syncSubjects() throws NotLoggedInErrorException, IOException, ParseException {
+    public void syncSubjects() throws VulcanException, IOException, ParseException {
         subjectSync.sync();
     }
 
     @Override
-    public void syncAttendance() throws NotLoggedInErrorException, ParseException, IOException {
+    public void syncAttendance() throws ParseException, IOException, VulcanException {
         attendanceSync.syncAttendance();
     }
 
     @Override
-    public void syncAttendance(String date) throws NotLoggedInErrorException, ParseException, IOException {
+    public void syncAttendance(String date) throws ParseException, IOException, VulcanException {
         attendanceSync.syncAttendance(date);
     }
 
     @Override
-    public void syncTimetable() throws NotLoggedInErrorException, IOException, ParseException {
+    public void syncTimetable() throws VulcanException, IOException, ParseException {
         timetableSync.syncTimetable();
     }
 
     @Override
-    public void syncTimetable(String date) throws NotLoggedInErrorException, IOException, ParseException {
+    public void syncTimetable(String date) throws VulcanException, IOException, ParseException {
         timetableSync.syncTimetable(date);
     }
 
     @Override
-    public void syncAll() throws NotLoggedInErrorException, IOException, ParseException {
+    public void syncAll() throws VulcanException, IOException, ParseException {
         syncSubjects();
         syncGrades();
         syncAttendance();
diff --git a/app/src/main/java/io/github/wulkanowy/data/RepositoryContract.java b/app/src/main/java/io/github/wulkanowy/data/RepositoryContract.java
index 90aaeef8..f06c4762 100644
--- a/app/src/main/java/io/github/wulkanowy/data/RepositoryContract.java
+++ b/app/src/main/java/io/github/wulkanowy/data/RepositoryContract.java
@@ -6,26 +6,26 @@ import java.util.List;
 
 import javax.inject.Singleton;
 
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
+import io.github.wulkanowy.api.VulcanException;
 import io.github.wulkanowy.data.db.dao.entities.Account;
 import io.github.wulkanowy.data.db.dao.entities.Grade;
 import io.github.wulkanowy.data.db.dao.entities.Week;
 import io.github.wulkanowy.data.db.resources.ResourcesContract;
+import io.github.wulkanowy.data.sync.account.AccountSyncContract;
 import io.github.wulkanowy.data.sync.attendance.AttendanceSyncContract;
-import io.github.wulkanowy.data.sync.login.LoginSyncContract;
 import io.github.wulkanowy.data.sync.timetable.TimetableSyncContract;
 
 @Singleton
-public interface RepositoryContract extends ResourcesContract, LoginSyncContract,
+public interface RepositoryContract extends ResourcesContract, AccountSyncContract,
         AttendanceSyncContract, TimetableSyncContract {
 
     long getCurrentUserId();
 
-    void syncGrades() throws NotLoggedInErrorException, IOException, ParseException;
+    void syncGrades() throws VulcanException, IOException, ParseException;
 
-    void syncSubjects() throws NotLoggedInErrorException, IOException, ParseException;
+    void syncSubjects() throws VulcanException, IOException, ParseException;
 
-    void syncAll() throws NotLoggedInErrorException, IOException, ParseException;
+    void syncAll() throws VulcanException, IOException, ParseException;
 
     Account getCurrentUser();
 
diff --git a/app/src/main/java/io/github/wulkanowy/data/db/resources/AppResources.java b/app/src/main/java/io/github/wulkanowy/data/db/resources/AppResources.java
index e9b85464..349ac177 100644
--- a/app/src/main/java/io/github/wulkanowy/data/db/resources/AppResources.java
+++ b/app/src/main/java/io/github/wulkanowy/data/db/resources/AppResources.java
@@ -11,8 +11,8 @@ import javax.inject.Inject;
 import javax.inject.Singleton;
 
 import io.github.wulkanowy.R;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
-import io.github.wulkanowy.api.login.VulcanOfflineException;
+import io.github.wulkanowy.api.NotLoggedInErrorException;
+import io.github.wulkanowy.api.VulcanOfflineException;
 import io.github.wulkanowy.data.db.dao.entities.AttendanceLesson;
 import io.github.wulkanowy.di.annotations.ApplicationContext;
 import io.github.wulkanowy.utils.AppConstant;
diff --git a/app/src/main/java/io/github/wulkanowy/data/sync/SyncContract.java b/app/src/main/java/io/github/wulkanowy/data/sync/SyncContract.java
index 43b37b7e..d9850ab1 100644
--- a/app/src/main/java/io/github/wulkanowy/data/sync/SyncContract.java
+++ b/app/src/main/java/io/github/wulkanowy/data/sync/SyncContract.java
@@ -3,9 +3,9 @@ package io.github.wulkanowy.data.sync;
 import java.io.IOException;
 import java.text.ParseException;
 
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
+import io.github.wulkanowy.api.VulcanException;
 
 public interface SyncContract {
 
-    void sync() throws NotLoggedInErrorException, IOException, ParseException;
+    void sync() throws VulcanException, IOException, ParseException;
 }
diff --git a/app/src/main/java/io/github/wulkanowy/data/sync/login/LoginSync.java b/app/src/main/java/io/github/wulkanowy/data/sync/account/AccountSync.java
similarity index 56%
rename from app/src/main/java/io/github/wulkanowy/data/sync/login/LoginSync.java
rename to app/src/main/java/io/github/wulkanowy/data/sync/account/AccountSync.java
index 71838ff5..d56f9990 100644
--- a/app/src/main/java/io/github/wulkanowy/data/sync/login/LoginSync.java
+++ b/app/src/main/java/io/github/wulkanowy/data/sync/account/AccountSync.java
@@ -1,4 +1,4 @@
-package io.github.wulkanowy.data.sync.login;
+package io.github.wulkanowy.data.sync.account;
 
 import android.content.Context;
 
@@ -8,10 +8,7 @@ import javax.inject.Inject;
 import javax.inject.Singleton;
 
 import io.github.wulkanowy.api.Vulcan;
-import io.github.wulkanowy.api.login.AccountPermissionException;
-import io.github.wulkanowy.api.login.BadCredentialsException;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
-import io.github.wulkanowy.api.login.VulcanOfflineException;
+import io.github.wulkanowy.api.VulcanException;
 import io.github.wulkanowy.data.db.dao.entities.Account;
 import io.github.wulkanowy.data.db.dao.entities.DaoSession;
 import io.github.wulkanowy.data.db.shared.SharedPrefContract;
@@ -21,7 +18,7 @@ import io.github.wulkanowy.utils.security.CryptoException;
 import io.github.wulkanowy.utils.security.Scrambler;
 
 @Singleton
-public class LoginSync implements LoginSyncContract {
+public class AccountSync implements AccountSyncContract {
 
     private final DaoSession daoSession;
 
@@ -32,8 +29,8 @@ public class LoginSync implements LoginSyncContract {
     private final Context context;
 
     @Inject
-    LoginSync(DaoSession daoSession, SharedPrefContract sharedPref,
-              Vulcan vulcan, @ApplicationContext Context context) {
+    AccountSync(DaoSession daoSession, SharedPrefContract sharedPref,
+                Vulcan vulcan, @ApplicationContext Context context) {
         this.daoSession = daoSession;
         this.sharedPref = sharedPref;
         this.vulcan = vulcan;
@@ -41,13 +38,12 @@ public class LoginSync implements LoginSyncContract {
     }
 
     @Override
-    public void loginUser(String email, String password, String symbol)
-            throws NotLoggedInErrorException, AccountPermissionException, IOException,
-            CryptoException, VulcanOfflineException, BadCredentialsException {
+    public void registerUser(String email, String password, String symbol)
+            throws VulcanException, IOException, CryptoException {
 
-        LogUtils.debug("Login new user email=" + email);
+        LogUtils.debug("Register new user email=" + email);
 
-        vulcan.login(email, password, symbol);
+        vulcan.setCredentials(email, password, symbol, null);
 
         Account account = new Account()
                 .setName(vulcan.getBasicInformation().getPersonalData().getFirstAndLastName())
@@ -56,24 +52,25 @@ public class LoginSync implements LoginSyncContract {
                 .setSymbol(vulcan.getSymbol())
                 .setSnpId(vulcan.getStudentAndParent().getId());
 
-        sharedPref.setCurrentUserId(daoSession.getAccountDao().insert(account));
+        daoSession.getAccountDao().insert(account);
+
+        sharedPref.setCurrentUserId(account.getId());
     }
 
     @Override
-    public void loginCurrentUser() throws NotLoggedInErrorException, AccountPermissionException,
-            IOException, CryptoException, VulcanOfflineException, BadCredentialsException {
+    public void initLastUser() throws VulcanException, IOException, CryptoException {
 
         long userId = sharedPref.getCurrentUserId();
 
         if (userId == 0) {
-            throw new IOException("Can't find logged user");
+            throw new IOException("Can't find saved user");
         }
 
-        LogUtils.debug("Login current user id=" + userId);
+        LogUtils.debug("Initialization current user id=" + userId);
 
         Account account = daoSession.getAccountDao().load(userId);
 
-        vulcan.login(account.getEmail(),
+        vulcan.setCredentials(account.getEmail(),
                 Scrambler.decrypt(account.getEmail(), account.getPassword()),
                 account.getSymbol(),
                 account.getSnpId());
diff --git a/app/src/main/java/io/github/wulkanowy/data/sync/account/AccountSyncContract.java b/app/src/main/java/io/github/wulkanowy/data/sync/account/AccountSyncContract.java
new file mode 100644
index 00000000..799d320e
--- /dev/null
+++ b/app/src/main/java/io/github/wulkanowy/data/sync/account/AccountSyncContract.java
@@ -0,0 +1,16 @@
+package io.github.wulkanowy.data.sync.account;
+
+import java.io.IOException;
+
+import io.github.wulkanowy.api.VulcanException;
+import io.github.wulkanowy.utils.security.CryptoException;
+
+public interface AccountSyncContract {
+
+    void registerUser(String email, String password, String symbol)
+            throws VulcanException, IOException,
+            CryptoException;
+
+    void initLastUser() throws VulcanException, IOException,
+            CryptoException;
+}
diff --git a/app/src/main/java/io/github/wulkanowy/data/sync/attendance/AttendanceSync.java b/app/src/main/java/io/github/wulkanowy/data/sync/attendance/AttendanceSync.java
index 19de88ef..325fff19 100644
--- a/app/src/main/java/io/github/wulkanowy/data/sync/attendance/AttendanceSync.java
+++ b/app/src/main/java/io/github/wulkanowy/data/sync/attendance/AttendanceSync.java
@@ -9,8 +9,8 @@ import javax.inject.Inject;
 import javax.inject.Singleton;
 
 import io.github.wulkanowy.api.Vulcan;
+import io.github.wulkanowy.api.VulcanException;
 import io.github.wulkanowy.api.generic.Lesson;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
 import io.github.wulkanowy.data.db.dao.entities.AttendanceLesson;
 import io.github.wulkanowy.data.db.dao.entities.AttendanceLessonDao;
 import io.github.wulkanowy.data.db.dao.entities.DaoSession;
@@ -42,12 +42,12 @@ public class AttendanceSync implements AttendanceSyncContract {
     }
 
     @Override
-    public void syncAttendance() throws IOException, NotLoggedInErrorException, ParseException {
+    public void syncAttendance() throws IOException, ParseException, VulcanException {
         syncAttendance(null);
     }
 
     @Override
-    public void syncAttendance(String date) throws IOException, NotLoggedInErrorException, ParseException {
+    public void syncAttendance(String date) throws IOException, ParseException, VulcanException {
         this.userId = sharedPref.getCurrentUserId();
 
         io.github.wulkanowy.api.generic.Week<io.github.wulkanowy.api.generic.Day> weekApi = getWeekFromApi(getNormalizedDate(date));
@@ -59,7 +59,7 @@ public class AttendanceSync implements AttendanceSyncContract {
 
         daoSession.getAttendanceLessonDao().saveInTx(lessonList);
 
-        LogUtils.debug("Synchronization lessons (amount = " + lessonList.size() + ")");
+        LogUtils.debug("Synchronization attendance lessons (amount = " + lessonList.size() + ")");
     }
 
     private String getNormalizedDate(String date) throws ParseException {
@@ -67,7 +67,7 @@ public class AttendanceSync implements AttendanceSyncContract {
     }
 
     private io.github.wulkanowy.api.generic.Week<io.github.wulkanowy.api.generic.Day> getWeekFromApi(String date)
-            throws IOException, NotLoggedInErrorException, ParseException {
+            throws IOException, ParseException, VulcanException {
         return vulcan.getAttendanceTable().getWeekTable(date);
     }
 
diff --git a/app/src/main/java/io/github/wulkanowy/data/sync/attendance/AttendanceSyncContract.java b/app/src/main/java/io/github/wulkanowy/data/sync/attendance/AttendanceSyncContract.java
index 503086ba..dfb4c1b4 100644
--- a/app/src/main/java/io/github/wulkanowy/data/sync/attendance/AttendanceSyncContract.java
+++ b/app/src/main/java/io/github/wulkanowy/data/sync/attendance/AttendanceSyncContract.java
@@ -3,11 +3,11 @@ package io.github.wulkanowy.data.sync.attendance;
 import java.io.IOException;
 import java.text.ParseException;
 
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
+import io.github.wulkanowy.api.VulcanException;
 
 public interface AttendanceSyncContract {
 
-    void syncAttendance(String date) throws NotLoggedInErrorException, IOException, ParseException;
+    void syncAttendance(String date) throws IOException, ParseException, VulcanException;
 
-    void syncAttendance() throws NotLoggedInErrorException, IOException, ParseException;
+    void syncAttendance() throws IOException, ParseException, VulcanException;
 }
diff --git a/app/src/main/java/io/github/wulkanowy/data/sync/grades/GradeSync.java b/app/src/main/java/io/github/wulkanowy/data/sync/grades/GradeSync.java
index e0b38884..b132ac1b 100644
--- a/app/src/main/java/io/github/wulkanowy/data/sync/grades/GradeSync.java
+++ b/app/src/main/java/io/github/wulkanowy/data/sync/grades/GradeSync.java
@@ -9,7 +9,7 @@ import javax.inject.Inject;
 import javax.inject.Singleton;
 
 import io.github.wulkanowy.api.Vulcan;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
+import io.github.wulkanowy.api.VulcanException;
 import io.github.wulkanowy.data.db.dao.entities.Account;
 import io.github.wulkanowy.data.db.dao.entities.DaoSession;
 import io.github.wulkanowy.data.db.dao.entities.Grade;
@@ -29,6 +29,8 @@ public class GradeSync implements SyncContract {
 
     private final SharedPrefContract sharedPref;
 
+    private Long userId;
+
     @Inject
     GradeSync(DaoSession daoSession, SharedPrefContract sharedPref, Vulcan vulcan) {
         this.daoSession = daoSession;
@@ -37,36 +39,53 @@ public class GradeSync implements SyncContract {
     }
 
     @Override
-    public void sync() throws IOException, NotLoggedInErrorException, ParseException {
+    public void sync() throws IOException, VulcanException, ParseException {
 
-        long userId = sharedPref.getCurrentUserId();
+        userId = sharedPref.getCurrentUserId();
 
         Account account = daoSession.getAccountDao().load(userId);
-        account.resetGradeList();
-        account.resetSubjectList();
+        resetAccountRelations(account);
 
-        List<Grade> gradesFromNet = DataObjectConverter
-                .gradesToGradeEntities(vulcan.getGradesList().getAll());
-        List<Grade> gradesFromDb = account.getGradeList();
-
-        List<Grade> updatedGrades = EntitiesCompare.compareGradeList(gradesFromNet, gradesFromDb);
-
-        daoSession.getGradeDao().deleteInTx(gradesFromDb);
-
-        List<Grade> lastList = new ArrayList<>();
-
-        for (Grade grade : updatedGrades) {
-            grade.setUserId(userId);
-            grade.setSubjectId(daoSession.getSubjectDao().queryBuilder()
-                    .where(SubjectDao.Properties.Name.eq(grade.getSubject()),
-                            SubjectDao.Properties.UserId.eq(userId))
-                    .build()
-                    .uniqueOrThrow().getId());
-            lastList.add(grade);
-        }
+        List<Grade> lastList = getUpdatedList(getComparedList(account));
 
+        daoSession.getGradeDao().deleteInTx(account.getGradeList());
         daoSession.getGradeDao().insertInTx(lastList);
 
         LogUtils.debug("Synchronization grades (amount = " + lastList.size() + ")");
     }
+
+    private void resetAccountRelations(Account account) {
+        account.resetSubjectList();
+        account.resetGradeList();
+    }
+
+    private List<Grade> getUpdatedList(List<Grade> comparedList) {
+        List<Grade> updatedList = new ArrayList<>();
+
+        for (Grade grade : comparedList) {
+            grade.setUserId(userId);
+            grade.setSubjectId(getSubjectId(grade.getSubject()));
+            updatedList.add(grade);
+        }
+        return updatedList;
+    }
+
+    private List<Grade> getComparedList(Account account) throws IOException, VulcanException,
+            ParseException {
+        List<Grade> gradesFromNet = DataObjectConverter
+                .gradesToGradeEntities(vulcan.getGradesList().getAll());
+
+        List<Grade> gradesFromDb = account.getGradeList();
+
+        return EntitiesCompare.compareGradeList(gradesFromNet, gradesFromDb);
+    }
+
+    private Long getSubjectId(String subjectName) {
+        return daoSession.getSubjectDao().queryBuilder()
+                .where(SubjectDao.Properties.Name.eq(subjectName),
+                        SubjectDao.Properties.UserId.eq(userId))
+                .build()
+                .uniqueOrThrow()
+                .getId();
+    }
 }
diff --git a/app/src/main/java/io/github/wulkanowy/data/sync/login/LoginSyncContract.java b/app/src/main/java/io/github/wulkanowy/data/sync/login/LoginSyncContract.java
deleted file mode 100644
index 1aed8b1b..00000000
--- a/app/src/main/java/io/github/wulkanowy/data/sync/login/LoginSyncContract.java
+++ /dev/null
@@ -1,19 +0,0 @@
-package io.github.wulkanowy.data.sync.login;
-
-import java.io.IOException;
-
-import io.github.wulkanowy.api.login.AccountPermissionException;
-import io.github.wulkanowy.api.login.BadCredentialsException;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
-import io.github.wulkanowy.api.login.VulcanOfflineException;
-import io.github.wulkanowy.utils.security.CryptoException;
-
-public interface LoginSyncContract {
-
-    void loginUser(String email, String password, String symbol)
-            throws NotLoggedInErrorException, AccountPermissionException, IOException,
-            CryptoException, VulcanOfflineException, BadCredentialsException;
-
-    void loginCurrentUser() throws NotLoggedInErrorException, AccountPermissionException, IOException,
-            CryptoException, VulcanOfflineException, BadCredentialsException;
-}
diff --git a/app/src/main/java/io/github/wulkanowy/data/sync/subjects/SubjectSync.java b/app/src/main/java/io/github/wulkanowy/data/sync/subjects/SubjectSync.java
index d888090b..1c5bfc71 100644
--- a/app/src/main/java/io/github/wulkanowy/data/sync/subjects/SubjectSync.java
+++ b/app/src/main/java/io/github/wulkanowy/data/sync/subjects/SubjectSync.java
@@ -9,10 +9,10 @@ import javax.inject.Inject;
 import javax.inject.Singleton;
 
 import io.github.wulkanowy.api.Vulcan;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
+import io.github.wulkanowy.api.VulcanException;
+import io.github.wulkanowy.data.db.dao.entities.Account;
 import io.github.wulkanowy.data.db.dao.entities.DaoSession;
 import io.github.wulkanowy.data.db.dao.entities.Subject;
-import io.github.wulkanowy.data.db.dao.entities.SubjectDao;
 import io.github.wulkanowy.data.db.shared.SharedPrefContract;
 import io.github.wulkanowy.data.sync.SyncContract;
 import io.github.wulkanowy.utils.DataObjectConverter;
@@ -21,41 +21,51 @@ import io.github.wulkanowy.utils.LogUtils;
 @Singleton
 public class SubjectSync implements SyncContract {
 
-    private final SubjectDao subjectDao;
+    private final DaoSession daoSession;
 
     private final Vulcan vulcan;
 
     private final SharedPrefContract sharedPref;
 
+    private Long userId;
+
     @Inject
     SubjectSync(DaoSession daoSession, SharedPrefContract sharedPref, Vulcan vulcan) {
-        this.subjectDao = daoSession.getSubjectDao();
+        this.daoSession = daoSession;
         this.sharedPref = sharedPref;
         this.vulcan = vulcan;
     }
 
     @Override
-    public void sync() throws NotLoggedInErrorException, IOException, ParseException {
+    public void sync() throws VulcanException, IOException, ParseException {
 
-        long userId = sharedPref.getCurrentUserId();
+        userId = sharedPref.getCurrentUserId();
 
-        List<Subject> subjectsFromNet = DataObjectConverter
-                .subjectsToSubjectEntities(vulcan.getSubjectsList().getAll());
+        List<Subject> lastList = getUpdatedList(getSubjectsFromNet());
 
-        subjectDao.deleteInTx(subjectDao.queryBuilder()
-                .where(SubjectDao.Properties.UserId.eq(userId))
-                .build()
-                .list());
-
-        List<Subject> lastList = new ArrayList<>();
-
-        for (Subject subject : subjectsFromNet) {
-            subject.setUserId(userId);
-            lastList.add(subject);
-        }
-
-        subjectDao.insertInTx(lastList);
+        daoSession.getSubjectDao().deleteInTx(getSubjectsFromDb());
+        daoSession.getSubjectDao().insertInTx(lastList);
 
         LogUtils.debug("Synchronization subjects (amount = " + lastList.size() + ")");
     }
+
+    private List<Subject> getSubjectsFromNet() throws VulcanException, IOException {
+        return DataObjectConverter.subjectsToSubjectEntities(vulcan.getSubjectsList().getAll());
+    }
+
+    private List<Subject> getSubjectsFromDb() {
+        Account account = daoSession.getAccountDao().load(userId);
+        account.resetSubjectList();
+        return account.getSubjectList();
+    }
+
+    private List<Subject> getUpdatedList(List<Subject> subjectsFromNet) {
+        List<Subject> updatedList = new ArrayList<>();
+
+        for (Subject subject : subjectsFromNet) {
+            subject.setUserId(userId);
+            updatedList.add(subject);
+        }
+        return updatedList;
+    }
 }
diff --git a/app/src/main/java/io/github/wulkanowy/data/sync/timetable/TimetableSync.java b/app/src/main/java/io/github/wulkanowy/data/sync/timetable/TimetableSync.java
index 11819bed..da6b143f 100644
--- a/app/src/main/java/io/github/wulkanowy/data/sync/timetable/TimetableSync.java
+++ b/app/src/main/java/io/github/wulkanowy/data/sync/timetable/TimetableSync.java
@@ -9,8 +9,8 @@ import javax.inject.Inject;
 import javax.inject.Singleton;
 
 import io.github.wulkanowy.api.Vulcan;
+import io.github.wulkanowy.api.VulcanException;
 import io.github.wulkanowy.api.generic.Lesson;
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
 import io.github.wulkanowy.data.db.dao.entities.DaoSession;
 import io.github.wulkanowy.data.db.dao.entities.Day;
 import io.github.wulkanowy.data.db.dao.entities.DayDao;
@@ -42,12 +42,12 @@ public class TimetableSync implements TimetableSyncContract {
     }
 
     @Override
-    public void syncTimetable() throws NotLoggedInErrorException, IOException, ParseException {
+    public void syncTimetable() throws IOException, ParseException, VulcanException {
         syncTimetable(null);
     }
 
     @Override
-    public void syncTimetable(String date) throws NotLoggedInErrorException, IOException, ParseException {
+    public void syncTimetable(String date) throws IOException, ParseException, VulcanException {
         this.userId = sharedPref.getCurrentUserId();
 
         io.github.wulkanowy.api.generic.Week<io.github.wulkanowy.api.generic.Day> weekApi = getWeekFromApi(getNormalizedDate(date));
@@ -59,7 +59,7 @@ public class TimetableSync implements TimetableSyncContract {
 
         daoSession.getTimetableLessonDao().saveInTx(lessonList);
 
-        LogUtils.debug("Synchronization lessons (amount = " + lessonList.size() + ")");
+        LogUtils.debug("Synchronization timetable lessons (amount = " + lessonList.size() + ")");
     }
 
     private String getNormalizedDate(String date) throws ParseException {
@@ -67,7 +67,7 @@ public class TimetableSync implements TimetableSyncContract {
     }
 
     private io.github.wulkanowy.api.generic.Week<io.github.wulkanowy.api.generic.Day> getWeekFromApi(String date)
-            throws IOException, NotLoggedInErrorException, ParseException {
+            throws IOException, VulcanException, ParseException {
         return vulcan.getTimetable().getWeekTable(date);
     }
 
diff --git a/app/src/main/java/io/github/wulkanowy/data/sync/timetable/TimetableSyncContract.java b/app/src/main/java/io/github/wulkanowy/data/sync/timetable/TimetableSyncContract.java
index 4c37d2ec..9bba209a 100644
--- a/app/src/main/java/io/github/wulkanowy/data/sync/timetable/TimetableSyncContract.java
+++ b/app/src/main/java/io/github/wulkanowy/data/sync/timetable/TimetableSyncContract.java
@@ -3,11 +3,11 @@ package io.github.wulkanowy.data.sync.timetable;
 import java.io.IOException;
 import java.text.ParseException;
 
-import io.github.wulkanowy.api.login.NotLoggedInErrorException;
+import io.github.wulkanowy.api.VulcanException;
 
 public interface TimetableSyncContract {
 
-    void syncTimetable(String date) throws NotLoggedInErrorException, IOException, ParseException;
+    void syncTimetable(String date) throws VulcanException, IOException, ParseException;
 
-    void syncTimetable() throws NotLoggedInErrorException, IOException, ParseException;
+    void syncTimetable() throws VulcanException, IOException, ParseException;
 }
diff --git a/app/src/main/java/io/github/wulkanowy/di/modules/ApplicationModule.java b/app/src/main/java/io/github/wulkanowy/di/modules/ApplicationModule.java
index 46744c90..e7d2bcc6 100644
--- a/app/src/main/java/io/github/wulkanowy/di/modules/ApplicationModule.java
+++ b/app/src/main/java/io/github/wulkanowy/di/modules/ApplicationModule.java
@@ -21,11 +21,11 @@ import io.github.wulkanowy.data.db.resources.ResourcesContract;
 import io.github.wulkanowy.data.db.shared.SharedPref;
 import io.github.wulkanowy.data.db.shared.SharedPrefContract;
 import io.github.wulkanowy.data.sync.SyncContract;
+import io.github.wulkanowy.data.sync.account.AccountSync;
+import io.github.wulkanowy.data.sync.account.AccountSyncContract;
 import io.github.wulkanowy.data.sync.attendance.AttendanceSync;
 import io.github.wulkanowy.data.sync.attendance.AttendanceSyncContract;
 import io.github.wulkanowy.data.sync.grades.GradeSync;
-import io.github.wulkanowy.data.sync.login.LoginSync;
-import io.github.wulkanowy.data.sync.login.LoginSyncContract;
 import io.github.wulkanowy.data.sync.subjects.SubjectSync;
 import io.github.wulkanowy.data.sync.timetable.TimetableSync;
 import io.github.wulkanowy.data.sync.timetable.TimetableSyncContract;
@@ -100,8 +100,8 @@ public class ApplicationModule {
 
     @Singleton
     @Provides
-    LoginSyncContract provideLoginSync(LoginSync loginSync) {
-        return loginSync;
+    AccountSyncContract provideLoginSync(AccountSync accountSync) {
+        return accountSync;
     }
 
     @SyncGrades
diff --git a/app/src/main/java/io/github/wulkanowy/services/SyncJob.java b/app/src/main/java/io/github/wulkanowy/services/SyncJob.java
index ab26fcee..e7b0908f 100644
--- a/app/src/main/java/io/github/wulkanowy/services/SyncJob.java
+++ b/app/src/main/java/io/github/wulkanowy/services/SyncJob.java
@@ -62,7 +62,7 @@ public class SyncJob extends SimpleJobService {
     @Override
     public int onRunJob(JobParameters job) {
         try {
-            repository.loginCurrentUser();
+            repository.initLastUser();
             repository.syncAll();
 
             gradeList = repository.getNewGrades();
diff --git a/app/src/main/java/io/github/wulkanowy/ui/login/LoginContract.java b/app/src/main/java/io/github/wulkanowy/ui/login/LoginContract.java
index fa074896..debfbbde 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/login/LoginContract.java
+++ b/app/src/main/java/io/github/wulkanowy/ui/login/LoginContract.java
@@ -42,6 +42,8 @@ public interface LoginContract {
 
         void onStartAsync();
 
+        void onDoInBackground(int stepNumber) throws Exception;
+
         void onLoginProgress(int step);
 
         void onEndAsync(boolean success, Exception exception);
diff --git a/app/src/main/java/io/github/wulkanowy/ui/login/LoginPresenter.java b/app/src/main/java/io/github/wulkanowy/ui/login/LoginPresenter.java
index b4e2e4e9..2b6d173d 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/login/LoginPresenter.java
+++ b/app/src/main/java/io/github/wulkanowy/ui/login/LoginPresenter.java
@@ -17,6 +17,12 @@ public class LoginPresenter extends BasePresenter<LoginContract.View>
 
     private LoginTask loginAsync;
 
+    private String email;
+
+    private String password;
+
+    private String symbol;
+
     @Inject
     LoginPresenter(RepositoryContract repository) {
         super(repository);
@@ -26,17 +32,17 @@ public class LoginPresenter extends BasePresenter<LoginContract.View>
     public void attemptLogin(String email, String password, String symbol) {
         getView().resetViewErrors();
 
+        this.email = email;
+        this.password = password;
+        this.symbol = getNormalizedSymbol(symbol);
+
         if (!isAllFieldCorrect(password, email)) {
             getView().showSoftInput();
             return;
         }
 
         if (getView().isNetworkConnected()) {
-            // Dopóki używamy AsyncTask presenter będzie musiał "wiedzieć" o AsyncTaskach
-            loginAsync = new LoginTask(this,
-                    email,
-                    password,
-                    getNormalizedSymbol(symbol));
+            loginAsync = new LoginTask(this);
             loginAsync.execute();
 
         } else {
@@ -53,6 +59,18 @@ public class LoginPresenter extends BasePresenter<LoginContract.View>
         }
     }
 
+    @Override
+    public void onDoInBackground(int stepNumber) throws Exception {
+        switch (stepNumber) {
+            case 1:
+                getRepository().registerUser(email, password, symbol);
+                break;
+            case 2:
+                getRepository().syncAll();
+                break;
+        }
+    }
+
     @Override
     public void onLoginProgress(int step) {
         if (step == 1) {
diff --git a/app/src/main/java/io/github/wulkanowy/ui/login/LoginTask.java b/app/src/main/java/io/github/wulkanowy/ui/login/LoginTask.java
index 441b8d8d..b22194da 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/login/LoginTask.java
+++ b/app/src/main/java/io/github/wulkanowy/ui/login/LoginTask.java
@@ -4,21 +4,12 @@ import android.os.AsyncTask;
 
 public class LoginTask extends AsyncTask<Void, Integer, Boolean> {
 
-    private String email;
-
-    private String password;
-
-    private String symbol;
-
     private LoginContract.Presenter presenter;
 
     private Exception exception;
 
-    LoginTask(LoginContract.Presenter presenter, String email, String password, String symbol) {
+    LoginTask(LoginContract.Presenter presenter) {
         this.presenter = presenter;
-        this.email = email;
-        this.password = password;
-        this.symbol = symbol;
     }
 
     @Override
@@ -30,10 +21,10 @@ public class LoginTask extends AsyncTask<Void, Integer, Boolean> {
     protected Boolean doInBackground(Void... params) {
         try {
             publishProgress(1);
-            presenter.getRepository().loginUser(email, password, symbol);
+            presenter.onDoInBackground(1);
 
             publishProgress(2);
-            presenter.getRepository().syncAll();
+            presenter.onDoInBackground(2);
         } catch (Exception e) {
             exception = e;
             return false;
diff --git a/app/src/main/java/io/github/wulkanowy/ui/main/attendance/AttendanceTabPresenter.java b/app/src/main/java/io/github/wulkanowy/ui/main/attendance/AttendanceTabPresenter.java
index 7f4766c9..d0d448ca 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/main/attendance/AttendanceTabPresenter.java
+++ b/app/src/main/java/io/github/wulkanowy/ui/main/attendance/AttendanceTabPresenter.java
@@ -153,7 +153,6 @@ public class AttendanceTabPresenter extends BasePresenter<AttendanceTabContract.
     }
 
     private void syncData() throws Exception {
-        getRepository().loginCurrentUser();
         getRepository().syncAttendance(date);
     }
 
diff --git a/app/src/main/java/io/github/wulkanowy/ui/main/grades/GradesPresenter.java b/app/src/main/java/io/github/wulkanowy/ui/main/grades/GradesPresenter.java
index 65c8acd0..8bdad12a 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/main/grades/GradesPresenter.java
+++ b/app/src/main/java/io/github/wulkanowy/ui/main/grades/GradesPresenter.java
@@ -71,7 +71,6 @@ public class GradesPresenter extends BasePresenter<GradesContract.View>
 
     @Override
     public void onDoInBackgroundRefresh() throws Exception {
-        getRepository().loginCurrentUser();
         getRepository().syncSubjects();
         getRepository().syncGrades();
     }
diff --git a/app/src/main/java/io/github/wulkanowy/ui/main/timetable/TimetableTabPresenter.java b/app/src/main/java/io/github/wulkanowy/ui/main/timetable/TimetableTabPresenter.java
index 00dcef6a..e5eb499f 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/main/timetable/TimetableTabPresenter.java
+++ b/app/src/main/java/io/github/wulkanowy/ui/main/timetable/TimetableTabPresenter.java
@@ -157,7 +157,6 @@ public class TimetableTabPresenter extends BasePresenter<TimetableTabContract.Vi
     }
 
     private void syncData() throws Exception {
-        getRepository().loginCurrentUser();
         getRepository().syncTimetable(date);
     }
 
diff --git a/app/src/main/java/io/github/wulkanowy/ui/splash/SplashPresenter.java b/app/src/main/java/io/github/wulkanowy/ui/splash/SplashPresenter.java
index c3d81215..d617b4af 100644
--- a/app/src/main/java/io/github/wulkanowy/ui/splash/SplashPresenter.java
+++ b/app/src/main/java/io/github/wulkanowy/ui/splash/SplashPresenter.java
@@ -6,6 +6,7 @@ import javax.inject.Inject;
 
 import io.github.wulkanowy.data.RepositoryContract;
 import io.github.wulkanowy.ui.base.BasePresenter;
+import io.github.wulkanowy.utils.LogUtils;
 
 public class SplashPresenter extends BasePresenter<SplashContract.View>
         implements SplashContract.Presenter {
@@ -23,7 +24,12 @@ public class SplashPresenter extends BasePresenter<SplashContract.View>
         if (getRepository().getCurrentUserId() == 0) {
             getView().openLoginActivity();
         } else {
-            getView().openMainActivity();
+            try {
+                getRepository().initLastUser();
+                getView().openMainActivity();
+            } catch (Exception e) {
+                LogUtils.error("An error occurred when the application was started", e);
+            }
         }
     }
 }
diff --git a/app/src/test/java/io/github/wulkanowy/utils/DataObjectConverterTest.java b/app/src/test/java/io/github/wulkanowy/utils/DataObjectConverterTest.java
index f32877c5..b0335f62 100644
--- a/app/src/test/java/io/github/wulkanowy/utils/DataObjectConverterTest.java
+++ b/app/src/test/java/io/github/wulkanowy/utils/DataObjectConverterTest.java
@@ -6,10 +6,10 @@ import org.junit.Test;
 import java.util.ArrayList;
 import java.util.List;
 
-import io.github.wulkanowy.api.grades.Grade;
-import io.github.wulkanowy.api.grades.Subject;
 import io.github.wulkanowy.api.generic.Day;
 import io.github.wulkanowy.api.generic.Lesson;
+import io.github.wulkanowy.api.grades.Grade;
+import io.github.wulkanowy.api.grades.Subject;
 import io.github.wulkanowy.data.db.dao.entities.TimetableLesson;
 
 public class DataObjectConverterTest {