FileName = "c:\" & DateTime.Now.ToString("dd_MM_yyyy") & ".Err.log"
 
        If Not File.Exists(FileName) Then
            File.CreateText(FileName).Close()
        End If
        swr = New StreamWriter(FileName, True, Encoding.Default)
        swr.WriteLine(DateTime.Now.Hour.ToString & ":" & _
          DateTime.Now.Minute.ToString & " --> " & strfunktion & " ; " & _
          strdata)     ' Schreiben der Daten
        swr.Close()