<System.Runtime.InteropServices.ComVisible(True)> _
 Public Sub Serverstart()
        Using PipeServer As New  _
          NamedPipeServerStream(PipeName, PipeDirection.InOut, _
          maxNumberOfServerinstances, PipeTransmissionMode.Message, _
          PipeOptions.Asynchronous)
 
            ZeileAnzeigen("Server: --> warte auf Client..." & " PipeName = " _
              & PipeName)
            PipeServer.WaitForConnection()
            ZeileAnzeigen("Server: --> verbunden")
            PipeOn = True
            While PipeOn
                Try
                    If Not PipeServer.IsConnected Then Serverstart()
                    Using sr As New StreamReader(PipeServer), sw As New _
                      StreamWriter(PipeServer)
                        sw.AutoFlush = True
                        Dim temp As String = String.Empty
                        tcOut = Nothing
                        While (assign(temp, sr.ReadLine())) IsNot Nothing
                            ServerInput = temp
                            If ServerInput.Length > 0 Then RaiseEvent _
                              PropertyChanged(Me, ServerRequest)
                            If Not tcOut Is Nothing Then
                                Dim bf As New BinaryFormatter
                                bf.Serialize(PipeServer, tcOut)
                            End If
                        End While
                        ZeileAnzeigen("Server: --> Daten")
                    End Using
                    'End If
                Catch ex As Exception
                    ' kam Fehler bei beenden Client vor Server --> 
                    ' unterbrochene Pipe
                    ZeileAnzeigen("Server Fehler: --> " & _
                      ex.InnerException.ToString)
                End Try
            End While
            ZeileAnzeigen("Server: --> beende")
        End Using
        PipeOn = False
    End Sub

  <System.Runtime.InteropServices.ComVisible(True)> _
 Public Sub ClientStart(ByVal AnfrageString As String)
        Using PipeClient As New NamedPipeClientStream(ServerName, PipeName, _
          PipeDirection.InOut, PipeOptions.None, _
          Security.Principal.TokenImpersonationLevel.Impersonation)
            ZeileAnzeigen("Client: --> warte auf Server..." & "PipeName = " _
            & String.Concat(ServerName, ",", PipeName))
            PipeClient.Connect()
            startTimer()
            PipeOn = True
            ZeileAnzeigen("Client: --> verbunden")
            sw = New StreamWriter(PipeClient)
            sw.AutoFlush = True
            sw.WriteLine(AnfrageString)
            ZeileAnzeigen("Client Anfrage: --> " & AnfrageString)
            If Not PipeOn Then PipeClient.Close()
            'Direkte Deserialisierung der empfangenen TC-Instanz
            Dim bfc As New BinaryFormatter
            Dim tc As TransferDaten = CType(bfc.Deserialize(PipeClient), _
              TransferDaten)
            If Not tc Is Nothing Then ClientInput = tc : RaiseEvent _
            PropertyChanged(Me, ClientRequest) : TimeOut.Dispose()
            PipeClient.Close()
            ZeileAnzeigen("Client: --> beendet")
        End Using
    End Sub

    Private tcOut As TransferDaten
    Public TransferTyp As TransferTyp
    Public TransferDataTable As DataTable
    Public TransferString As String
    Public TransferNumber As Decimal
    Public TransferCount As Integer
    Public Sub createTransferdata()
        Try
            tcOut = New TransferDaten
            With tcOut
                .Typ = TransferTyp
                If Not String.IsNullOrEmpty(TransferString) Then .TString = _
                  TransferString
                Select Case TransferTyp
                    Case NamedPipe.TransferTyp.Count
                        .TCount = TransferCount
                    Case NamedPipe.TransferTyp.Table
                        .CTable = TransferDataTable
                    Case NamedPipe.TransferTyp.Decimal
                        .TNumber = TransferNumber
                End Select
            End With
        Catch ex As Exception
            tcOut = Nothing
        End Try
    End Sub

Danke für die Hilfe

Gruß Christian