diff --git a/app/src/main/java/pl/szczodrzynski/edziennik/data/api/Errors.kt b/app/src/main/java/pl/szczodrzynski/edziennik/data/api/Errors.kt
index 5738064c..eefc1d31 100644
--- a/app/src/main/java/pl/szczodrzynski/edziennik/data/api/Errors.kt
+++ b/app/src/main/java/pl/szczodrzynski/edziennik/data/api/Errors.kt
@@ -195,6 +195,7 @@ const val ERROR_VULCAN_HEBE_FIREBASE_ERROR                  = 362
 const val ERROR_VULCAN_HEBE_CERTIFICATE_GONE                = 363
 const val ERROR_VULCAN_HEBE_SERVER_ERROR                    = 364
 const val ERROR_VULCAN_HEBE_ENTITY_NOT_FOUND                = 365
+const val ERROR_VULCAN_HEBE_MISSING_SENDER_ENTRY            = 366
 const val ERROR_VULCAN_API_DEPRECATED                       = 390
 
 const val ERROR_LOGIN_EDUDZIENNIK_WEB_INVALID_LOGIN         = 501
diff --git a/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/DataVulcan.kt b/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/DataVulcan.kt
index 55185745..e3516ad4 100644
--- a/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/DataVulcan.kt
+++ b/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/DataVulcan.kt
@@ -222,6 +222,16 @@ class DataVulcan(app: App, profile: Profile?, loginStore: LoginStore) : Data(app
         get() { mHebeContext = mHebeContext ?: profile?.getStudentData("hebeContext", null); return mHebeContext }
         set(value) { profile?.putStudentData("hebeContext", value) ?: return; mHebeContext = value }
 
+    private var mSenderAddressHash: String? = null
+    var senderAddressHash: String?
+        get() { mSenderAddressHash = mSenderAddressHash ?: profile?.getStudentData("senderAddressHash", null); return mSenderAddressHash }
+        set(value) { profile?.putStudentData("senderAddressHash", value) ?: return; mSenderAddressHash = value }
+
+    private var mSenderAddressName: String? = null
+    var senderAddressName: String?
+        get() { mSenderAddressName = mSenderAddressName ?: profile?.getStudentData("senderAddressName", null); return mSenderAddressName }
+        set(value) { profile?.putStudentData("senderAddressName", value) ?: return; mSenderAddressName = value }
+
     val apiUrl: String?
         get() {
             val url = when (apiToken[symbol]?.substring(0, 3)) {
diff --git a/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeMain.kt b/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeMain.kt
index c017e3c9..5e2d31c0 100644
--- a/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeMain.kt
+++ b/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeMain.kt
@@ -97,6 +97,10 @@ class VulcanHebeMain(
                 val studentSemesterId = period.getInt("Id") ?: return@forEach
                 val studentSemesterNumber = period.getInt("Number") ?: return@forEach
 
+                val senderEntry = student.getJsonObject("SenderEntry")
+                val senderAddressName = senderEntry.getString("Address")
+                val senderAddressHash = senderEntry.getString("AddressHash")
+
                 val hebeContext = student.getString("Context")
 
                 val isParent = login.getString("LoginRole").equals("opiekun", ignoreCase = true)
@@ -143,6 +147,8 @@ class VulcanHebeMain(
                     studentData["schoolSymbol"] = schoolSymbol
                     studentData["schoolShort"] = schoolShort
                     studentData["schoolName"] = schoolCode
+                    studentData["senderAddressName"] = senderAddressName
+                    studentData["senderAddressHash"] = senderAddressHash
                     studentData["hebeContext"] = hebeContext
                 }
                 dateSemester1Start?.let {
diff --git a/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeSendMessage.kt b/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeSendMessage.kt
index 8f5f5afa..c6a02ae7 100644
--- a/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeSendMessage.kt
+++ b/app/src/main/java/pl/szczodrzynski/edziennik/data/api/edziennik/vulcan/data/hebe/VulcanHebeSendMessage.kt
@@ -7,6 +7,7 @@ package pl.szczodrzynski.edziennik.data.api.edziennik.vulcan.data.hebe
 import com.google.gson.JsonObject
 import org.greenrobot.eventbus.EventBus
 import pl.szczodrzynski.edziennik.*
+import pl.szczodrzynski.edziennik.data.api.ERROR_VULCAN_HEBE_MISSING_SENDER_ENTRY
 import pl.szczodrzynski.edziennik.data.api.VULCAN_HEBE_ENDPOINT_MESSAGES_SEND
 import pl.szczodrzynski.edziennik.data.api.edziennik.vulcan.DataVulcan
 import pl.szczodrzynski.edziennik.data.api.edziennik.vulcan.data.VulcanHebe
@@ -27,6 +28,22 @@ class VulcanHebeSendMessage(
     }
 
     init {
+        if (data.senderAddressName == null || data.senderAddressHash == null) {
+            VulcanHebeMain(data).getStudents(data.profile, null) {
+                if (data.senderAddressName == null || data.senderAddressHash == null) {
+                    data.error(TAG, ERROR_VULCAN_HEBE_MISSING_SENDER_ENTRY)
+                }
+                else {
+                    sendMessage()
+                }
+            }
+        }
+        else {
+            sendMessage()
+        }
+    }
+
+    private fun sendMessage() {
         val recipientsArray = JsonArray()
         recipients.forEach { teacher ->
             recipientsArray += JsonObject(
@@ -40,10 +57,10 @@ class VulcanHebeSendMessage(
         val senderName = (profile?.accountName ?: profile?.studentNameLong)
             ?.swapFirstLastName() ?: ""
         val sender = JsonObject(
-            "Address" to senderName,
+            "Address" to data.senderAddressName,
             "LoginId" to data.studentLoginId.toString(),
             "Initials" to senderName.getNameInitials(),
-            "AddressHash" to senderName.sha1Hex()
+            "AddressHash" to data.senderAddressHash
         )
 
         apiPost(
diff --git a/app/src/main/res/values/errors.xml b/app/src/main/res/values/errors.xml
index d90af9ed..827227c5 100644
--- a/app/src/main/res/values/errors.xml
+++ b/app/src/main/res/values/errors.xml
@@ -165,6 +165,7 @@
     <string name="error_363" translatable="false">ERROR_VULCAN_HEBE_CERTIFICATE_GONE</string>
     <string name="error_364" translatable="false">ERROR_VULCAN_HEBE_SERVER_ERROR</string>
     <string name="error_365" translatable="false">ERROR_VULCAN_HEBE_ENTITY_NOT_FOUND</string>
+    <string name="error_366" translatable="false">ERROR_VULCAN_HEBE_MISSING_SENDER_ENTRY</string>
     <string name="error_390" translatable="false">ERROR_VULCAN_API_DEPRECATED</string>
 
     <string name="error_501" translatable="false">ERROR_LOGIN_EDUDZIENNIK_WEB_INVALID_LOGIN</string>
@@ -363,6 +364,7 @@
     <string name="error_363_reason">VULCAN®: urządzenie usunięte. Zaloguj się ponownie do dziennika.</string>
     <string name="error_364_reason">VULCAN®: błąd serwera. Dziennik może być przeciążony.</string>
     <string name="error_365_reason">VULCAN®: nie znaleziono bytu</string>
+    <string name="error_366_reason">Błąd wysyłania wiadomości - brak informacji o nadawcy.</string>
     <string name="error_390_reason">W związku z wygaszeniem aplikacji Dzienniczek+ przez firmę Vulcan, należy zalogować się ponownie.\n\nAby móc dalej korzystać z aplikacji Szkolny.eu, otwórz Ustawienia i wybierz opcję Dodaj nowego ucznia.\nNastępnie zaloguj się do dziennika Vulcan zgodnie z instrukcją.\n\nPrzepraszamy za niedogodności.</string>
 
     <string name="error_501_reason">Błędny email lub hasło</string>