Verbesserungen: Thread-Sicherheit, Logging, WCF-Updates

Die Änderungen umfassen: - Einführung von `ReaderWriterLockSlim` für Thread-Sicherheit. - Optimierung von `IsOnline` mit atomaren Operationen. - Verbesserte Reconnect-Logik und Fehlerbehandlung. - Neue Methoden für Datenbankoperationen (`GetDatatableByName` etc.). - Gemeinsame `ChannelFactory` zur Ressourcenschonung. - Logging-Verbesserungen mit präziseren Meldungen und Symbolen. - Aktualisierte WCF-Bindings für höhere Verbindungszahlen und kürzere Timeouts. - Aktualisierte Service-Referenzen mit asynchronen Methoden. - Bereinigung von veralteten Methoden und Eigenschaften. - Assembly-Version auf `2.8.0.0` aktualisiert.
2026-10-13 12:06:50 +02:00
parent aad2f01490
commit 3eb6314ba8
9 changed files with 4244 additions and 659 deletions
--- a/EDMIAPI/Client.vb
+++ b/EDMIAPI/Client.vb
@@ -22,8 +22,45 @@ Public Class Client
    ' Runtime Variables
    Private _ServerAddress As ServerAddressStruct
    Private _ClientConfig As GlobalStateClientConfiguration
+
+    Private ReadOnly _CachedTablesLock As New ReaderWriterLockSlim()
    Private _CachedTables As New List(Of String)
-    Private _IsOnline As Boolean
+
+    Public ReadOnly Property CachedTables As List(Of String)
+        Get
+            _CachedTablesLock.EnterReadLock()
+            Try
+                Return _CachedTables.ToList() ' Snapshot zurückgeben
+            Finally
+                _CachedTablesLock.ExitReadLock()
+            End Try
+        End Get
+    End Property
+
+    ' Hilfsmethode – intern für alle Schreibzugriffe verwenden
+    Private Sub SetCachedTables(pTables As IEnumerable(Of String))
+        _CachedTablesLock.EnterWriteLock()
+        Try
+            _CachedTables = pTables.ToList()
+        Finally
+            _CachedTablesLock.ExitWriteLock()
+        End Try
+    End Sub
+    ' Ersetzt: Private _IsOnline As Boolean
+    Private _IsOnline As Integer = 0  ' 0 = offline, 1 = online  (Interlocked-kompatibel)
+    Public ReadOnly Property IsOnline As Boolean
+        Get
+            Return Interlocked.CompareExchange(_IsOnline, 0, 0) = 1
+        End Get
+    End Property
+    ' Setter-Hilfsmethoden für alle Schreibstellen:
+    Private Sub SetOnline()
+        Interlocked.Exchange(_IsOnline, 1)
+    End Sub
+
+    Private Sub SetOffline()
+        Interlocked.Exchange(_IsOnline, 0)
+    End Sub
    ' Verhindert parallele Reconnect-Versuche (0 = frei, 1 = läuft)
    Private _IsReconnecting As Integer = 0
    Private _Channel As IEDMIServiceChannel
@@ -56,14 +93,14 @@ Public Class Client
    Protected Overridable Sub Dispose(disposing As Boolean)
        If _Disposed Then Return
        If disposing Then
-            _IsOnline = False          ' ← Reconnect-Guard deaktivieren
+            SetOffline()
            UpdateTimer.Stop()
            UpdateTimer.Dispose()

            ' Auf laufenden Reconnect warten
            Dim oTimeout = DateTime.Now.AddSeconds(5)
            While _IsReconnecting = 1 AndAlso DateTime.Now < oTimeout
-                Task.Delay(100).Wait()
+                Thread.Sleep(100)
            End While

            If _Channel IsNot Nothing Then
@@ -71,6 +108,8 @@ Public Class Client
                _Channel = Nothing
            End If

+            _CachedTablesLock.Dispose()  ' ← NEU: Lock freigeben
+
            Dim oRemoved As ClientStatus = Nothing
            _ActiveClients.TryRemove(_ClientId, oRemoved)
            Logger.Debug("Client [{0}] unregistered. Total active clients: [{1}]", _ClientName, _ActiveClients.Count)
@@ -79,11 +118,6 @@ Public Class Client
    End Sub

    ' Public Variables
-    Public ReadOnly Property CachedTables
-        Get
-            Return _CachedTables
-        End Get
-    End Property

    Public ReadOnly Property ClientConfig As GlobalStateClientConfiguration
        Get
@@ -94,13 +128,6 @@ Public Class Client
            Return _ClientConfig
        End Get
    End Property
-
-    Public ReadOnly Property IsOnline As Boolean
-        Get
-            Return _IsOnline
-        End Get
-    End Property
-
    Public ReadOnly Property ServerAddress As String
        Get
            Return $"{_ServerAddress.Host}:{_ServerAddress.Port}"
@@ -197,14 +224,14 @@ Public Class Client
            ' CachedTables sofort befüllen – nicht auf den ersten Timer-Tick warten
            Try
                Dim oTables As String() = _Channel.GetCachedTables()
-                _CachedTables = oTables.Select(Function(t) t.ToUpper).ToList()
-                Logger.Debug("✔ CachedTables loaded on connect: [{0}]", _CachedTables.Count)
+                SetCachedTables(oTables.Select(Function(t) t.ToUpper()))
+                Logger.Debug("✔ CachedTables loaded on connect: [{0}]", CachedTables.Count)
            Catch ex As Exception
                Logger.Warn("⚠ CachedTables could not be loaded on connect: {0}", ex.Message)
-                _CachedTables = New List(Of String)
+                SetCachedTables(Enumerable.Empty(Of String)())
            End Try

-            _IsOnline = True              ' ← vor GetStatus()
+            SetOnline()
            UpdateTimer.Start()

            ' In Registry eintragen – jetzt mit korrektem IsOnline=True
@@ -213,7 +240,7 @@ Public Class Client

            Return True
        Catch ex As Exception
-            _IsOnline = False
+            SetOffline()
            Logger.Error(ex)
            Return False
        End Try
@@ -243,7 +270,7 @@ Public Class Client
                    _Channel = ChannelManager.GetChannel()
                    _Channel.Open()

-                    _IsOnline = True
+                    SetOnline()

                    If _ActiveClients.ContainsKey(_ClientId) Then
                        _ActiveClients(_ClientId) = GetStatus()
@@ -253,7 +280,7 @@ Public Class Client
                    Return
                Catch ex As Exception
                    Logger.Warn("⚠ Reconnect failed after [{0}]s: {1}", oDelay, ex.Message)
-                    _IsOnline = False
+                    SetOffline()
                End Try
            Next

@@ -266,53 +293,51 @@ Public Class Client

    Private Async Sub UpdateTimer_Elapsed(sender As Object, e As Timers.ElapsedEventArgs) Handles UpdateTimer.Elapsed
        Try
-            If _Channel Is Nothing OrElse _Channel.State <> CommunicationState.Opened Then
-                Logger.Warn("⚠ UpdateTimer skipped: Channel not in Opened state [{0}]", If(_Channel IsNot Nothing, _Channel.State.ToString(), "null"))
-                _IsOnline = False
+            ' ← Snapshot VOR dem Await – schützt gegen _Channel = Nothing nach Resume
+            Dim oChannel = _Channel
+            If oChannel Is Nothing OrElse oChannel.State <> CommunicationState.Opened Then
+                Logger.Warn("⚠ UpdateTimer skipped: Channel not in Opened state [{0}]",
+                            If(oChannel IsNot Nothing, oChannel.State.ToString(), "null"))
+                SetOffline()
                Reconnect(sender, e)
                Return
            End If

-            If Not _IsOnline Then
+            If Not IsOnline Then
                Logger.Debug("UpdateTimer skipped: Client is offline.")
                Return
            End If

-            Dim oTables As String() = Await _Channel.GetCachedTablesAsync()
-            ' ◄ NullReferenceException-Schutz: Service kann Nothing zurückgeben
+            Dim oTables As String() = Await oChannel.GetCachedTablesAsync() ' ← oChannel statt _Channel
+
            If oTables Is Nothing Then
                Logger.Warn("⚠ UpdateTimer: GetCachedTablesAsync returned Nothing.")
-                _CachedTables = New List(Of String)
+                SetCachedTables(Enumerable.Empty(Of String)())
                Return
            End If
-            _CachedTables = oTables.
-            Select(Function(table) table.ToUpper).
-            ToList()

+            SetCachedTables(oTables.Select(Function(table) table.ToUpper()))
+
+            ' ← oChannel.State statt _Channel.State
            Logger.Info("✔ Channel state: [{0}] | Active connections: [{1}] | CachedTables: [{2}]",
-            _Channel.State,
-            Channel.ActiveConnections,
-            _CachedTables.Count)
+                oChannel.State, Channel.ActiveConnections, CachedTables.Count)

            If _ActiveClients.ContainsKey(_ClientId) Then
                _ActiveClients(_ClientId) = GetStatus()
            End If

        Catch ex As TimeoutException
-            ' Stale TCP connection (z.B. Firewall/Citrix Idle-Timeout)
-            Logger.Warn("⚠ UpdateTimer: TCP connection lost (idle timeout / firewall). Triggering reconnect...")
-            _IsOnline = False
+            Logger.Warn("⚠ UpdateTimer: TCP connection lost. Triggering reconnect...")
+            SetOffline()
            Reconnect()
-
        Catch ex As CommunicationException
            Logger.Warn("⚠ UpdateTimer: Channel faulted. Triggering reconnect...")
-            _IsOnline = False
+            SetOffline()
            Reconnect()
-
        Catch ex As Exception
            Logger.Warn("⚠ Update of CachedTable was not successful!")
            Logger.Error(ex)
-            _CachedTables = New List(Of String)
+            SetCachedTables(Enumerable.Empty(Of String)())
        End Try
    End Sub

@@ -626,6 +651,59 @@ Public Class Client
    End Function

 #Region "GetDatatable"
+    Public Function GetDatatableByName(DatatableName As String, Optional FilterExpression As String = "", Optional SortByColumn As String = "") As TableResult
+        EnsureAvailable()
+        Try
+            Return _Channel.ReturnDatatableFromCache(DatatableName, FilterExpression, SortByColumn)
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetDatatableByName))
+        Catch ex As EndpointNotFoundException
+            HandleCommunicationError(ex, NameOf(GetDatatableByName))
+        Catch ex As CommunicationException
+            HandleCommunicationError(ex, NameOf(GetDatatableByName))
+        Catch ex As Exception
+            Logger.Error(ex)
+            Throw
+        End Try
+    End Function
+
+    Public Function GetScalarValueFromIDB(pSQL As String) As GetScalarValueResponse
+        EnsureAvailable()
+        Try
+            Return _Channel.ReturnScalarValue(New GetScalarValueRequest() With {
+                .SqlCommand = pSQL,
+                .NamedDatabase = DatabaseName.IDB
+            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetScalarValueFromIDB))
+        Catch ex As EndpointNotFoundException
+            HandleCommunicationError(ex, NameOf(GetScalarValueFromIDB))
+        Catch ex As CommunicationException
+            HandleCommunicationError(ex, NameOf(GetScalarValueFromIDB))
+        Catch ex As Exception
+            Logger.Error(ex)
+            Throw
+        End Try
+    End Function
+
+    Public Function ExecuteNonQueryFromIDB(pSQL As String) As ExecuteNonQueryResponse
+        EnsureAvailable()
+        Try
+            Return _Channel.ExecuteNonQuery(New ExecuteNonQueryRequest() With {
+                .SqlCommand = pSQL,
+                .NamedDatabase = DatabaseName.IDB
+            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromIDB))
+        Catch ex As EndpointNotFoundException
+            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromIDB))
+        Catch ex As CommunicationException
+            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromIDB))
+        Catch ex As Exception
+            Logger.Error(ex)
+            Throw
+        End Try
+    End Function
    Public Function GetDatatableFromIDB(pSQL As String) As GetDatatableResponse
        EnsureAvailable()
        Try
@@ -633,6 +711,8 @@ Public Class Client
                .SqlCommand = pSQL,
                .NamedDatabase = DatabaseName.IDB
            })
+        Catch ex As TimeoutException                          ' ← NEU
+            HandleCommunicationError(ex, NameOf(GetDatatableFromIDB))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetDatatableFromIDB))
        Catch ex As CommunicationException
@@ -643,6 +723,7 @@ Public Class Client
        End Try
    End Function

+    ' ── GetDatatable ──────────────────────────────────────────
    Public Function GetDatatableFromECM(pSQL As String) As GetDatatableResponse
        EnsureAvailable()
        Try
@@ -650,6 +731,8 @@ Public Class Client
                .SqlCommand = pSQL,
                .NamedDatabase = DatabaseName.ECM
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetDatatableFromECM))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetDatatableFromECM))
        Catch ex As CommunicationException
@@ -668,6 +751,8 @@ Public Class Client
                .NamedDatabase = DatabaseName.None,
                .ConnectionId = pConnectionId
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetDatatableFromConnection))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetDatatableFromConnection))
        Catch ex As CommunicationException
@@ -685,6 +770,8 @@ Public Class Client
                .SqlCommand = pSQL,
                .NamedDatabase = DatabaseName.IDB
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetDatatableFromIDBAsync))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetDatatableFromIDBAsync))
        Catch ex As CommunicationException
@@ -703,6 +790,8 @@ Public Class Client
                .SqlCommand = pSQL,
                .NamedDatabase = DatabaseName.ECM
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetDatatableFromECMAsync))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetDatatableFromECMAsync))
        Catch ex As CommunicationException
@@ -721,6 +810,8 @@ Public Class Client
                .NamedDatabase = DatabaseName.None,
                .ConnectionId = pConnectionId
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetDatatableFromConnectionAsync))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetDatatableFromConnectionAsync))
        Catch ex As CommunicationException
@@ -730,26 +821,8 @@ Public Class Client
            Throw
        End Try
    End Function
-#End Region
-
-#Region "GetScalarValue"
-    Public Function GetScalarValueFromIDB(pSQL As String) As GetScalarValueResponse
-        EnsureAvailable()
-        Try
-            Return _Channel.ReturnScalarValue(New GetScalarValueRequest() With {
-                .SqlCommand = pSQL,
-                .NamedDatabase = DatabaseName.IDB
-            })
-        Catch ex As EndpointNotFoundException
-            HandleCommunicationError(ex, NameOf(GetScalarValueFromIDB))
-        Catch ex As CommunicationException
-            HandleCommunicationError(ex, NameOf(GetScalarValueFromIDB))
-        Catch ex As Exception
-            Logger.Error(ex)
-            Throw
-        End Try
-    End Function

+    ' ── GetScalarValue ─────────────────────────────────────────
    Public Function GetScalarValueFromECM(pSQL As String) As GetScalarValueResponse
        EnsureAvailable()
        Try
@@ -757,6 +830,8 @@ Public Class Client
                .SqlCommand = pSQL,
                .NamedDatabase = DatabaseName.ECM
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetScalarValueFromECM))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetScalarValueFromECM))
        Catch ex As CommunicationException
@@ -775,6 +850,8 @@ Public Class Client
                .NamedDatabase = DatabaseName.None,
                .ConnectionId = pConnectionId
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetScalarValueFromConnection))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetScalarValueFromConnection))
        Catch ex As CommunicationException
@@ -792,6 +869,8 @@ Public Class Client
                .SqlCommand = pSQL,
                .NamedDatabase = DatabaseName.IDB
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetScalarValueFromIDBAsync))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetScalarValueFromIDBAsync))
        Catch ex As CommunicationException
@@ -809,6 +888,8 @@ Public Class Client
                .SqlCommand = pSQL,
                .NamedDatabase = DatabaseName.ECM
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetScalarValueFromECMAsync))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetScalarValueFromECMAsync))
        Catch ex As CommunicationException
@@ -827,6 +908,8 @@ Public Class Client
                .NamedDatabase = DatabaseName.None,
                .ConnectionId = pConnectionId
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetScalarValueFromConnectionAsync))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(GetScalarValueFromConnectionAsync))
        Catch ex As CommunicationException
@@ -836,26 +919,8 @@ Public Class Client
            Throw
        End Try
    End Function
-#End Region
-
-#Region "ExecuteNonQuery"
-    Public Function ExecuteNonQueryFromIDB(pSQL As String) As ExecuteNonQueryResponse
-        EnsureAvailable()
-        Try
-            Return _Channel.ExecuteNonQuery(New ExecuteNonQueryRequest() With {
-                .SqlCommand = pSQL,
-                .NamedDatabase = DatabaseName.IDB
-            })
-        Catch ex As EndpointNotFoundException
-            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromIDB))
-        Catch ex As CommunicationException
-            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromIDB))
-        Catch ex As Exception
-            Logger.Error(ex)
-            Throw
-        End Try
-    End Function

+    ' ── ExecuteNonQuery ────────────────────────────────────────
    Public Function ExecuteNonQueryFromECM(pSQL As String) As ExecuteNonQueryResponse
        EnsureAvailable()
        Try
@@ -863,6 +928,8 @@ Public Class Client
                .SqlCommand = pSQL,
                .NamedDatabase = DatabaseName.ECM
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromECM))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromECM))
        Catch ex As CommunicationException
@@ -881,6 +948,8 @@ Public Class Client
                .NamedDatabase = DatabaseName.None,
                .ConnectionId = pConnectionId
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromConnection))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromConnection))
        Catch ex As CommunicationException
@@ -898,6 +967,8 @@ Public Class Client
                .SqlCommand = pSQL,
                .NamedDatabase = DatabaseName.IDB
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromIDBAsync))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromIDBAsync))
        Catch ex As CommunicationException
@@ -915,6 +986,8 @@ Public Class Client
                .SqlCommand = pSQL,
                .NamedDatabase = DatabaseName.ECM
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromECMAsync))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromECMAsync))
        Catch ex As CommunicationException
@@ -933,6 +1006,8 @@ Public Class Client
                .NamedDatabase = DatabaseName.None,
                .ConnectionId = pConnectionId
            })
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromConnectionAsync))
        Catch ex As EndpointNotFoundException
            HandleCommunicationError(ex, NameOf(ExecuteNonQueryFromConnectionAsync))
        Catch ex As CommunicationException
@@ -942,45 +1017,26 @@ Public Class Client
            Throw
        End Try
    End Function
+
+    ' ── Sonstige ───────────────────────────────────────────────
+    Public Async Function GetDatatableByNameAsync(DatatableName As String, Optional FilterExpression As String = "", Optional SortByColumn As String = "") As Task(Of TableResult)
+        EnsureAvailable()
+        Try
+            Return Await _Channel.ReturnDatatableFromCacheAsync(DatatableName, FilterExpression, SortByColumn)
+        Catch ex As TimeoutException
+            HandleCommunicationError(ex, NameOf(GetDatatableByNameAsync))
+        Catch ex As EndpointNotFoundException
+            HandleCommunicationError(ex, NameOf(GetDatatableByNameAsync))
+        Catch ex As CommunicationException
+            HandleCommunicationError(ex, NameOf(GetDatatableByNameAsync))
+        Catch ex As Exception
+            Logger.Error(ex)
+            Throw
+        End Try
+    End Function
 #End Region


-    Public Function GetDatatableByName(DatatableName As String, Optional FilterExpression As String = "", Optional SortByColumn As String = "") As TableResult
-        EnsureAvailable()
-        Try
-            Return _Channel.ReturnDatatableFromCache(DatatableName, FilterExpression, SortByColumn)
-        Catch ex As EndpointNotFoundException
-            HandleCommunicationError(ex, NameOf(GetDatatableByName))
-        Catch ex As CommunicationException
-            HandleCommunicationError(ex, NameOf(GetDatatableByName))
-        Catch ex As Exception
-            Logger.Error(ex)
-            Throw
-        End Try
-    End Function
-
-    Public Async Function GetDatatableByNameAsync(DatatableName As String, Optional FilterExpression As String = "", Optional SortByColumn As String = "") As Task(Of TableResult)
-        EnsureAvailable()
-        Try
-            Return Await _Channel.ReturnDatatableFromCacheAsync(DatatableName, FilterExpression, SortByColumn)
-        Catch ex As EndpointNotFoundException
-            HandleCommunicationError(ex, NameOf(GetDatatableByNameAsync))
-        Catch ex As CommunicationException
-            HandleCommunicationError(ex, NameOf(GetDatatableByNameAsync))
-        Catch ex As Exception
-            Logger.Error(ex)
-            Throw
-        End Try
-    End Function
-
-
-
-    ''' <summary>
-    ''' Return infos about a file object
-    ''' </summary>
-    ''' <param name="UserId"></param>
-    ''' <param name="ObjectId"></param>
-    ''' <returns></returns>
    Public Function GetDocumentInfo(UserId As Long, ObjectId As Long) As DocumentInfo
        Try
            Dim oResponse As DocumentInfoResponse = _Channel.GetFileInfoByObjectId(New DocumentInfoRequest With {
@@ -1056,27 +1112,25 @@ Public Class Client
            Throw New InvalidOperationException("Channel is not initialized. Call Connect() first.")
        End If

-        If Not _IsOnline Then
-            ' Kurze Grace-Period abwarten, damit Reconnect() seinen _IsReconnecting-Flag setzen kann
-            Dim oGraceLimit = DateTime.Now.AddMilliseconds(600)
-            While DateTime.Now < oGraceLimit AndAlso _IsReconnecting = 0 AndAlso Not _IsOnline
-                Task.Delay(100).Wait()
-            End While
+        If Not IsOnline Then
+            ' Wenn Reconnect aktiv läuft: kurze Grace-Period (max 1s) statt 10s
+            If _IsReconnecting = 1 Then
+                Dim oGraceLimit = DateTime.Now.AddMilliseconds(1000)
+                While DateTime.Now < oGraceLimit AndAlso Not IsOnline
+                    Thread.Sleep(100)
+                End While
+            End If

-            ' Jetzt auf aktiven Reconnect warten
-            Dim oWaitLimit = DateTime.Now.AddSeconds(10)
-            While Not _IsOnline AndAlso DateTime.Now < oWaitLimit AndAlso _IsReconnecting = 1
-                Task.Delay(500).Wait()
-                Logger.Debug("EnsureAvailable: Waiting for reconnect... Channel=[{0}]", _Channel.State.ToString())
-            End While
-
-            If Not _IsOnline Then
-                Throw New InvalidOperationException("Client is offline.")
+            ' Danach sofort werfen – WCF-Timeout nicht weiter aufbrauchen
+            If Not IsOnline Then
+                Throw New InvalidOperationException(
+                    $"Client is offline. Reconnect in progress=[{_IsReconnecting = 1}].")
            End If
        End If

        If _Channel.State <> CommunicationState.Opened Then
-            Throw New InvalidOperationException($"Channel is not available. State=[{_Channel.State}]")
+            Throw New InvalidOperationException(
+                $"Channel is not available. State=[{_Channel.State}]")
        End If
    End Sub
    ''' <summary>
@@ -1084,6 +1138,8 @@ Public Class Client
    ''' </summary>
    Private Sub HandleCommunicationError(ex As Exception, callerName As String)
        Select Case True
+            Case TypeOf ex Is TimeoutException
+                Logger.Warn("⚠ TimeoutException in [{0}]. Channel may be stale. Triggering reconnect...", callerName)
            Case TypeOf ex Is EndpointNotFoundException
                Logger.Warn("⚠ Service not reachable (EndpointNotFoundException in [{0}]). Triggering reconnect...", callerName)
            Case TypeOf ex Is CommunicationException
@@ -1093,7 +1149,7 @@ Public Class Client
                Logger.Error(ex)
        End Select

-        _IsOnline = False
+        SetOffline()
        Reconnect()
        Throw ex
    End Sub
@@ -1190,15 +1246,16 @@ Public Class Client
    ''' Returns a detailed status snapshot of the current client state
    ''' </summary>
    Public Function GetStatus() As ClientStatus
+        Dim oTables = CachedTables ' ← Property nutzen: enthält Read-Lock + Snapshot
        Return New ClientStatus() With {
-            .IsOnline = _IsOnline,
-            .ClientId = _ClientId,      ' ← Neu
+            .IsOnline = IsOnline,              ' ← Property statt Feld
+            .ClientId = _ClientId,
            .ClientName = _ClientName,
            .ServerAddress = Me.ServerAddress,
            .ChannelState = If(_Channel IsNot Nothing, _Channel.State.ToString(), "null"),
            .ActiveConnections = Channel.ActiveConnections,
-            .CachedTableCount = _CachedTables.Count,
-            .CachedTables = _CachedTables.ToList(),
+            .CachedTableCount = oTables.Count, ' ← aus Snapshot
+            .CachedTables = oTables,           ' ← aus Snapshot
            .HasClientConfig = _ClientConfig IsNot Nothing,
            .IsDisposed = _Disposed,
            .TimerEnabled = UpdateTimer.Enabled,
--- a/EDMIAPI/Client/Channel.vb
+++ b/EDMIAPI/Client/Channel.vb
@@ -8,10 +8,14 @@ Imports DigitalData.Modules.Logging
 Public Class Channel
    Inherits BaseClass

+    Private Shared ReadOnly _FactoryLock As New Object()
+    Private Shared _SharedFactory As ChannelFactory(Of IEDMIServiceChannel) = Nothing
+    Private Shared _SharedFactoryEndpoint As String = String.Empty
+
    Private ReadOnly ChannelFactory As ChannelFactory(Of IEDMIServiceChannel)

    Public Event Reconnect As EventHandler
-    ' Verbindungszähler
+
    Private Shared _ActiveConnections As Integer = 0
    Public Shared ReadOnly Property ActiveConnections As Integer
        Get
@@ -20,40 +24,91 @@ Public Class Channel
    End Property

    Public Shared Function GetBinding(Optional AuthenticationMode As TcpClientCredentialType = TcpClientCredentialType.Windows) As NetTcpBinding
+        Dim oMaxConnections = Math.Max(500, Environment.ProcessorCount * 50)
+
        Return New NetTcpBinding() With {
-        .MaxReceivedMessageSize = Constants.ChannelSettings.MAX_RECEIVED_MESSAGE_SIZE,
-        .MaxBufferSize = Constants.ChannelSettings.MAX_BUFFER_SIZE,
-        .MaxBufferPoolSize = Constants.ChannelSettings.MAX_BUFFER_POOL_SIZE,
-        .ListenBacklog = Constants.ChannelSettings.MAX_CONNECTIONS,
-        .MaxConnections = Constants.ChannelSettings.MAX_CONNECTIONS,
-        .TransferMode = TransferMode.Streamed,
-        .SendTimeout = TimeSpan.FromSeconds(30),      ' ← War: 5min → Schnellere Fehlererkennung
-        .ReceiveTimeout = TimeSpan.FromMinutes(10),   ' Keepalive < Firewall-Timeout (3600s) ✓
-        .OpenTimeout = TimeSpan.FromSeconds(30),      ' ← Neu: Verbindungsaufbau begrenzen
-        .CloseTimeout = TimeSpan.FromSeconds(30),
-        .Security = New NetTcpSecurity() With {
-            .Mode = SecurityMode.Transport,
-            .Transport = New TcpTransportSecurity() With {
-                .ClientCredentialType = AuthenticationMode
+            .MaxReceivedMessageSize = Constants.ChannelSettings.MAX_RECEIVED_MESSAGE_SIZE,
+            .MaxBufferSize = Constants.ChannelSettings.MAX_BUFFER_SIZE,
+            .MaxBufferPoolSize = Constants.ChannelSettings.MAX_BUFFER_POOL_SIZE,
+            .ListenBacklog = oMaxConnections,
+            .MaxConnections = oMaxConnections,
+            .TransferMode = TransferMode.Streamed,
+            .SendTimeout = TimeSpan.FromSeconds(60),
+            .ReceiveTimeout = TimeSpan.FromMinutes(10),
+            .OpenTimeout = TimeSpan.FromSeconds(60),
+            .CloseTimeout = TimeSpan.FromSeconds(30),
+            .Security = New NetTcpSecurity() With {
+                .Mode = SecurityMode.Transport,
+                .Transport = New TcpTransportSecurity() With {
+                    .ClientCredentialType = AuthenticationMode
+                }
+            },
+            .ReaderQuotas = New XmlDictionaryReaderQuotas() With {
+                .MaxArrayLength = Constants.ChannelSettings.MAX_ARRAY_LENGTH,
+                .MaxStringContentLength = Constants.ChannelSettings.MAX_STRING_CONTENT_LENGTH
            }
-        },
-        .ReaderQuotas = New XmlDictionaryReaderQuotas() With {
-            .MaxArrayLength = Constants.ChannelSettings.MAX_ARRAY_LENGTH,
-            .MaxStringContentLength = Constants.ChannelSettings.MAX_STRING_CONTENT_LENGTH
        }
-    }
    End Function

    Public Sub New(pLogConfig As LogConfig, pServerAddress As ServerAddressStruct)
        MyBase.New(pLogConfig)
-        ChannelFactory = GetChannelFactory(pServerAddress)
+        ChannelFactory = GetOrCreateSharedFactory(pLogConfig, pServerAddress)
    End Sub
+
+    ''' <summary>
+    ''' Gibt eine gemeinsame ChannelFactory zurück.
+    ''' Ein Connection-Pool für alle Client-Instanzen desselben Endpoints.
+    ''' </summary>
+    Private Shared Function GetOrCreateSharedFactory(pLogConfig As LogConfig, pServerAddress As ServerAddressStruct) As ChannelFactory(Of IEDMIServiceChannel)
+        Dim oEndpoint = $"net.tcp://{pServerAddress.Host}:{pServerAddress.Port}/DigitalData/Services/Main"
+
+        ' ← Volatile.Read: garantiert aktuellen Wert auch ohne Lock
+        Dim oCurrentFactory = Volatile.Read(_SharedFactory)
+        If oCurrentFactory IsNot Nothing AndAlso
+           _SharedFactoryEndpoint = oEndpoint AndAlso
+           (oCurrentFactory.State = CommunicationState.Opened OrElse
+            oCurrentFactory.State = CommunicationState.Created) Then
+            Return oCurrentFactory
+        End If
+
+        SyncLock _FactoryLock
+            ' Double-check nach Lock
+            If _SharedFactory IsNot Nothing AndAlso
+               _SharedFactoryEndpoint = oEndpoint AndAlso
+               (_SharedFactory.State = CommunicationState.Opened OrElse
+                _SharedFactory.State = CommunicationState.Created) Then
+                Return _SharedFactory
+            End If
+
+            If _SharedFactory IsNot Nothing Then
+                If _SharedFactory.State = CommunicationState.Faulted OrElse
+                   _SharedFactory.State = CommunicationState.Closing Then
+                    Try
+                        _SharedFactory.Abort()
+                    Catch
+                    End Try
+                End If
+                _SharedFactory = Nothing
+            End If
+
+            Dim oLogger = pLogConfig.GetLogger()
+            Dim oBinding = GetBinding()
+            Dim oAddress = New EndpointAddress(oEndpoint)
+
+            oLogger.Debug("Creating shared ChannelFactory | Endpoint=[{0}] | MaxConnections=[{1}] | SendTimeout=[{2}] | OpenTimeout=[{3}]",
+                oEndpoint, oBinding.MaxConnections, oBinding.SendTimeout, oBinding.OpenTimeout)
+
+            _SharedFactory = New ChannelFactory(Of IEDMIServiceChannel)(oBinding, oAddress)
+            _SharedFactoryEndpoint = oEndpoint
+            Return _SharedFactory
+        End SyncLock
+    End Function
+
    ''' <summary>
    ''' Closes a channel gracefully, falls back to Abort on error
    ''' </summary>
    Public Shared Sub CloseChannel(pChannel As IEDMIServiceChannel)
        If pChannel Is Nothing Then Return
-
        Try
            If pChannel.State = CommunicationState.Opened Then
                pChannel.Close()
@@ -61,31 +116,27 @@ Public Class Channel
                   pChannel.State = CommunicationState.Closing Then
                pChannel.Abort()
            End If
-            ' CommunicationState.Created / Closed → nichts tun, Zähler nicht betroffen
        Catch ex As Exception
            Try
                pChannel.Abort()
            Catch
-                ' Ignore
            End Try
        End Try
    End Sub
+
    ''' <summary>
    ''' Creates a channel and adds a Faulted-Handler
    ''' </summary>
-    ''' <returns>A channel object</returns>
    Public Function GetChannel() As IEDMIServiceChannel
        Try
-            Logger.Debug("Creating channel.")
+            Logger.Debug("Creating channel from shared factory.")
            Dim oChannel = ChannelFactory.CreateChannel()

-            ' Verbindung zählen beim Öffnen
            AddHandler oChannel.Opened, Sub()
                                            Dim oCount = Interlocked.Increment(_ActiveConnections)
                                            Logger.Debug("Channel opened. Active connections: [{0}]", oCount)
                                        End Sub

-            ' Verbindung abziehen beim Schließen oder Fehler
            AddHandler oChannel.Closed, Sub()
                                            Dim oCount = Interlocked.Decrement(_ActiveConnections)
                                            Logger.Debug("Channel closed. Active connections: [{0}]", oCount)
@@ -93,7 +144,7 @@ Public Class Channel

            AddHandler oChannel.Faulted, Sub()
                                             Dim oCount = Interlocked.Decrement(_ActiveConnections)
-                                             Logger.Warn("Channel faulted. Active connections: [{0}]", oCount)
+                                             Logger.Warn("⚠ Channel faulted. Active connections: [{0}]", oCount)
                                             RaiseEvent Reconnect(Me, Nothing)
                                         End Sub

@@ -104,20 +155,4 @@ Public Class Channel
            Throw
        End Try
    End Function
-
-    Private Function GetChannelFactory(pServerAddress As ServerAddressStruct) As ChannelFactory(Of IEDMIServiceChannel)
-        Dim oBinding = GetBinding()
-        Dim oAddress = New EndpointAddress($"net.tcp://{pServerAddress.Host}:{pServerAddress.Port}/DigitalData/Services/Main")
-        Logger.Debug("Creating ChannelFactory with Binding: SendTimeout=[{0}], ReceiveTimeout=[{1}], MaxConnections=[{2}], MaxBufferSize=[{3}], TransferMode=[{4}]",
-            oBinding.SendTimeout,
-            oBinding.ReceiveTimeout,
-            oBinding.MaxConnections,
-            oBinding.MaxBufferSize,
-            oBinding.TransferMode)
-        Dim oFactory = New ChannelFactory(Of IEDMIServiceChannel)(oBinding, oAddress)
-        Return oFactory
-    End Function
-
-End Class
-
-
+End Class
--- a/Services/EDMIServiceReference/Reference.svcmap
+++ b/Services/EDMIServiceReference/Reference.svcmap
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<ReferenceGroup xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" ID="1b516c6d-d2d0-4dfc-9557-3dd0593fa624" xmlns="urn:schemas-microsoft-com:xml-wcfservicemap">
+<ReferenceGroup xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" ID="1b516c6d-d2d0-4dfc-9557-3dd0593fa624" xmlns="urn:schemas-microsoft-com:xml-wcfservicemap">
  <ClientOptions>
    <GenerateAsynchronousMethods>false</GenerateAsynchronousMethods>
    <GenerateTaskBasedAsynchronousMethod>true</GenerateTaskBasedAsynchronousMethod>
--- a/Services/EDMIServiceReference/Reference.vb
+++ b/Services/EDMIServiceReference/Reference.vb
--- a/Services/EDMIServiceReference/configuration.svcinfo
+++ b/Services/EDMIServiceReference/configuration.svcinfo
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<configurationSnapshot xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="urn:schemas-microsoft-com:xml-wcfconfigurationsnapshot">
+<configurationSnapshot xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="urn:schemas-microsoft-com:xml-wcfconfigurationsnapshot">
  <behaviors />
  <bindings>
    <binding digest="System.ServiceModel.Configuration.NetTcpBindingElement, System.ServiceModel, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089:&lt;?xml version=&quot;1.0&quot; encoding=&quot;utf-16&quot;?&gt;&lt;Data name=&quot;NetTcpBinding_IEDMIService&quot; transferMode=&quot;Streamed&quot;&gt;&lt;security&gt;&lt;transport sslProtocols=&quot;None&quot; /&gt;&lt;/security&gt;&lt;/Data&gt;" bindingType="netTcpBinding" name="NetTcpBinding_IEDMIService" />
--- a/Services/EDMIServiceReference/configuration91.svcinfo
+++ b/Services/EDMIServiceReference/configuration91.svcinfo
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<SavedWcfConfigurationInformation xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" Version="9.1" CheckSum="LUfq4Z7qL259JRuSf1xmDS/kLlBkZTtgk2vJyQH0Jvo=">
+<SavedWcfConfigurationInformation xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" Version="9.1" CheckSum="4uBt9Y5m0Ue4fIPG6eooT5TT5MJ97hiEcthL6+tUJHw=">
  <bindingConfigurations>
    <bindingConfiguration bindingType="netTcpBinding" name="NetTcpBinding_IEDMIService">
      <properties>
--- a/EDMIAPI/DatabaseWithFallback.vb
+++ b/EDMIAPI/DatabaseWithFallback.vb
@@ -342,14 +342,17 @@ Public Class DatabaseWithFallback
    End Function

    Private Async Function GetDatatableFromServiceAsync(pSQLCommand As String, DatabaseType As Constants.DatabaseType, pConnectionId As Integer) As Task(Of DataTable)
-        Dim oFallback As Boolean = False
-        _Logger.Debug("GetDatatableFromServiceAsync: GetDatatableFromServiceAsync called with SQL [{0}], DatabaseType [{1}], ConnectionId [{2}]", pSQLCommand, DatabaseType.ToString, pConnectionId)
+        _Logger.Debug("GetDatatableFromServiceAsync called | SQL=[{0}] | DB=[{1}] | ConnId=[{2}]",
+                      pSQLCommand, DatabaseType.ToString, pConnectionId)
+
        If _Client Is Nothing OrElse _ClientConfig?.ForceDirectDatabaseAccess Then
-            Return Await Task.Run(Function() GetDatatableFromDatabase(pSQLCommand, DatabaseType, pConnectionId))
+            ' ← Kein Task.Run: direkt synchron, Thread ist ohnehin frei
+            Return GetDatatableFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
        End If

-        Dim oResult As GetDatatableResponse = Nothing
        Try
+            Dim oResult As GetDatatableResponse = Nothing
+
            Select Case DatabaseType
                Case Constants.DatabaseType.ECM
                    oResult = Await _Client.GetDatatableFromECMAsync(pSQLCommand)
@@ -360,20 +363,22 @@ Public Class DatabaseWithFallback
            End Select

            If oResult Is Nothing OrElse oResult.OK = False Then
-                _Logger.Warn("⚠ GetDatatableFromServiceAsync failed. Falling back to direct database access.")
-                oFallback = True
+                _Logger.Warn("⚠ GetDatatableFromServiceAsync failed | Fallback to DB | Error=[{0}]",
+                             If(oResult Is Nothing, "null", oResult.ErrorMessage))
+                Return GetDatatableFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
            End If
+
+            Return oResult.Table
+
+        Catch ex As InvalidOperationException
+            _Logger.Warn("⚠ GetDatatableFromServiceAsync offline: [{0}] | Fallback to DB", ex.Message)
+            Return GetDatatableFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
+
        Catch ex As Exception
-            _Logger.Warn("⚠ GetDatatableFromServiceAsync failed. Falling back to direct database access.")
+            _Logger.Warn("⚠ GetDatatableFromServiceAsync failed | Fallback to DB")
            _Logger.Error(ex)
-            oFallback = True
+            Return GetDatatableFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
        End Try
-
-        If oFallback Then
-            Return Await Task.Run(Function() GetDatatableFromDatabase(pSQLCommand, DatabaseType, pConnectionId))
-        End If
-
-        Return oResult.Table
    End Function
    Private Function GetDatatableFromDatabase(pSQLCommand As String, pDatabaseType As Constants.DatabaseType, pConnectionId As Integer) As DataTable
        Try
@@ -401,16 +406,16 @@ Public Class DatabaseWithFallback
        End Try
    End Function
    Private Async Function GetScalarValueFromServiceAsync(pSQLCommand As String, DatabaseType As Constants.DatabaseType, pConnectionId As Integer) As Task(Of Object)
-        Dim oFallback As Boolean = False
-
-        _Logger.Debug("GetScalarValueFromServiceAsync called with SQL [{0}], DatabaseType [{1}], ConnectionId [{2}]", pSQLCommand, DatabaseType.ToString, pConnectionId)
+        _Logger.Debug("GetScalarValueFromServiceAsync called | SQL=[{0}] | DB=[{1}] | ConnId=[{2}]",
+                      pSQLCommand, DatabaseType.ToString, pConnectionId)

        If _Client Is Nothing OrElse _ClientConfig?.ForceDirectDatabaseAccess Then
-            Return Await Task.Run(Function() GetScalarValueFromDatabase(pSQLCommand, DatabaseType, pConnectionId))
+            Return GetScalarValueFromDatabase(pSQLCommand, DatabaseType, pConnectionId) ' ← kein Task.Run
        End If

-        Dim oResult As GetScalarValueResponse = Nothing
        Try
+            Dim oResult As GetScalarValueResponse = Nothing
+
            Select Case DatabaseType
                Case Constants.DatabaseType.ECM
                    oResult = Await _Client.GetScalarValueFromECMAsync(pSQLCommand)
@@ -421,20 +426,21 @@ Public Class DatabaseWithFallback
            End Select

            If oResult Is Nothing OrElse oResult.OK = False Then
-                _Logger.Warn("⚠ GetScalarValueFromServiceAsync failed. Falling back to direct database access.")
-                oFallback = True
+                _Logger.Warn("⚠ GetScalarValueFromServiceAsync failed | Fallback to DB")
+                Return GetScalarValueFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
            End If
+
+            Return oResult.Scalar
+
+        Catch ex As InvalidOperationException
+            _Logger.Warn("⚠ GetScalarValueFromServiceAsync offline: [{0}] | Fallback to DB", ex.Message)
+            Return GetScalarValueFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
+
        Catch ex As Exception
-            _Logger.Warn("⚠ GetScalarValueFromServiceAsync failed. Falling back to direct database access.")
+            _Logger.Warn("⚠ GetScalarValueFromServiceAsync failed | Fallback to DB")
            _Logger.Error(ex)
-            oFallback = True
+            Return GetScalarValueFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
        End Try
-
-        If oFallback Then
-            Return Await Task.Run(Function() GetScalarValueFromDatabase(pSQLCommand, DatabaseType, pConnectionId))
-        End If
-
-        Return oResult.Scalar
    End Function
    Private Function GetScalarValueFromService(pSQLCommand As String, DatabaseType As Constants.DatabaseType, pConnectionId As Integer) As Object
        Try
@@ -493,16 +499,16 @@ Public Class DatabaseWithFallback
        End Try
    End Function
    Private Async Function ExecuteNonQueryFromServiceAsync(pSQLCommand As String, DatabaseType As Constants.DatabaseType, pConnectionId As Integer) As Task(Of Boolean)
-        Dim oFallback As Boolean = False
-
-        _Logger.Debug("ExecuteNonQueryFromServiceAsync called with SQL [{0}], DatabaseType [{1}], ConnectionId [{2}]", pSQLCommand, DatabaseType.ToString, pConnectionId)
+        _Logger.Debug("ExecuteNonQueryFromServiceAsync called | SQL=[{0}] | DB=[{1}] | ConnId=[{2}]",
+                      pSQLCommand, DatabaseType.ToString, pConnectionId)

        If _Client Is Nothing OrElse _ClientConfig?.ForceDirectDatabaseAccess Then
-            Return Await Task.Run(Function() ExecuteNonQueryFromDatabase(pSQLCommand, DatabaseType, pConnectionId))
+            Return ExecuteNonQueryFromDatabase(pSQLCommand, DatabaseType, pConnectionId) ' ← kein Task.Run
        End If

-        Dim oResult As ExecuteNonQueryResponse = Nothing
        Try
+            Dim oResult As ExecuteNonQueryResponse = Nothing
+
            Select Case DatabaseType
                Case Constants.DatabaseType.ECM
                    oResult = Await _Client.ExecuteNonQueryFromECMAsync(pSQLCommand)
@@ -513,20 +519,21 @@ Public Class DatabaseWithFallback
            End Select

            If oResult Is Nothing OrElse oResult.OK = False Then
-                _Logger.Warn("⚠ ExecuteNonQueryFromServiceAsync failed. Falling back to direct database access.")
-                oFallback = True
+                _Logger.Warn("⚠ ExecuteNonQueryFromServiceAsync failed | Fallback to DB")
+                Return ExecuteNonQueryFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
            End If
+
+            Return oResult.Result
+
+        Catch ex As InvalidOperationException
+            _Logger.Warn("⚠ ExecuteNonQueryFromServiceAsync offline: [{0}] | Fallback to DB", ex.Message)
+            Return ExecuteNonQueryFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
+
        Catch ex As Exception
-            _Logger.Warn("⚠ ExecuteNonQueryFromServiceAsync failed. Falling back to direct database access.")
+            _Logger.Warn("⚠ ExecuteNonQueryFromServiceAsync failed | Fallback to DB")
            _Logger.Error(ex)
-            oFallback = True
+            Return ExecuteNonQueryFromDatabase(pSQLCommand, DatabaseType, pConnectionId)
        End Try
-
-        If oFallback Then
-            Return Await Task.Run(Function() ExecuteNonQueryFromDatabase(pSQLCommand, DatabaseType, pConnectionId))
-        End If
-
-        Return oResult.Result
    End Function
    Private Function ExecuteNonQueryFromService(pSQLCommand As String, DatabaseType As Constants.DatabaseType, pConnectionId As Integer) As Boolean
        Try
--- a/Project/AssemblyInfo.vb
+++ b/Project/AssemblyInfo.vb
@@ -13,7 +13,7 @@ Imports System.Runtime.InteropServices
 <Assembly: AssemblyCompany("Digital Data")>
 <Assembly: AssemblyProduct("EDMIAPI")>
 <Assembly: AssemblyCopyright("Copyright © 2026")>
-<Assembly: AssemblyTrademark("2.7.0")>
+<Assembly: AssemblyTrademark("2.8.0")>

 <Assembly: ComVisible(False)>

@@ -31,5 +31,5 @@ Imports System.Runtime.InteropServices
 ' übernehmen, indem Sie "*" eingeben:
 ' <Assembly: AssemblyVersion("1.0.*")>

-<Assembly: AssemblyVersion("2.7.0.0")>
+<Assembly: AssemblyVersion("2.8.0.0")>
 <Assembly: AssemblyFileVersion("1.6.1.1")>
--- a/EDMIAPI/Reference.vb
+++ b/EDMIAPI/Reference.vb