Index: sources/cloudsync/CloudSyncController.cpp
===================================================================
diff -u -r79e076cece4ba503be6c3834eb68d1e5cb1b882f -r75219a6e89b20f405aad0c12c5aed5937118b2ad
--- sources/cloudsync/CloudSyncController.cpp	(.../CloudSyncController.cpp)	(revision 79e076cece4ba503be6c3834eb68d1e5cb1b882f)
+++ sources/cloudsync/CloudSyncController.cpp	(.../CloudSyncController.cpp)	(revision 75219a6e89b20f405aad0c12c5aed5937118b2ad)
@@ -312,6 +312,7 @@
     case eError_ParamMismatch   : text = tr( "CS Mismatch parameter count"              ) ; break;
     case eError_ParamMissing    : text = tr( "CS Missing parameter"                     ) ; break;
     case eError_NoHistory       : text = tr( "CS No history available"                  ) ; break;
+    case eError_Duplicate       : text = tr( "CS Duplicate data"                        ) ; break;
     case eError_LogFolder       : text = tr( "CS The log folder cannot be created."     ) ; break;
     case eError_LogFileInp      : text = tr( "CS Error writing to the input file."      ) ; break;
     case eError_CredentialFile  : text = tr( "CS The credentials file does not exist."  ) ; break;
@@ -350,6 +351,7 @@
     case eError_ParamMismatch   : info = QString( "[%1:%2/%3]"  ).arg( vErrorID ).arg( item(0) ).arg( item(1) ) ; break;
     case eError_ParamMissing    : info = QString( "[%1:%2/%3]"  ).arg( vErrorID ).arg( item(0) ).arg( item(1) ) ; break;
     case eError_NoHistory       : info = QString( "[%1:%2]"     ).arg( vErrorID ).arg( item(0) )                ; break;
+    case eError_Duplicate       : info = QString( "[%1:%2]"     ).arg( vErrorID ).arg( item(0) )                ; break;
     case eError_LogFolder       :                                                                               ; break;
     case eError_LogFileInp      :                                                                               ; break;
     case eError_CredentialFile  : info = QString( "[%1:%2]"     ).arg( vErrorID ).arg( item(0) )                ; break;
@@ -431,10 +433,21 @@
                .arg( msg )
                .arg( len )
                .arg( prm )
-               ;
+            ;
 }
 
 /*!
+ * \brief CloudSyncController::isDuplicate
+ * \param vMessage  - current action/messageID received.
+ * \param vData     - current data to compare with the history
+ * \return true if duplicate
+ */
+bool CloudSyncController::isDuplicate(const qint32 vMessageID, const QStringList &vData)
+{
+    return _uiHistory.contains(vMessageID) && _uiHistory[vMessageID] == vData;
+}
+
+/*!
  * \brief   CloudSyncController::writeInpFile
  * \details Writes to the CS Input buffer
  * \param   vBuffer - the string out buffer.
@@ -497,12 +510,12 @@
     qint32 messageID = UI2CS(static_cast<MessageID_Enum>(vAction));
     QStringList data;
 
-    if ( vData.isEmpty() ) { error = eError_NoHistory; args = { messageID }; ok = false; goto lErr; }
+    if ( vData.isEmpty()                ) { error = eError_NoHistory; args = { messageID }; ok = false; goto lErr; }
 
-    // convert the data to string list
-    for (auto datum : vData) {
-        data += datum.toString();
-    }
+    data = Format::fromVariantList(vData);
+
+    if ( isDuplicate(messageID, data)   ) { error = eError_Duplicate; args = { messageID }; ok = false; return ok; } // goto lErr; } don't log it just ignore and return false.
+
     // store the last message data
     _uiHistory[messageID] = data;
 
@@ -556,8 +569,8 @@
     // case GuiActionType::ID_PostTreatmentStates  : // has not been discussed how to be sent out.
     // case GuiActionType::ID_DisinfectStates      : // has not been discussed how to be sent out.
     case GuiActionType::ID_HDOperationModeData  :
-        saveUIHistory(eMessageID_DeviceState    , vData );
-        sendUIHistory(eMessageID_DeviceState            ); // can be removed if CS doesn't need it.
+        if (saveUIHistory(eMessageID_DeviceState    , vData )) // if not empty, nor duplicate, and saved
+            sendUIHistory(eMessageID_DeviceState            );
     break;
 
     case GuiActionType::ID_AdjustSerialHDRsp    :