Function DateiExists(ByVal sDN As String)
 
        Dim fn As Integer
 
        fn% = FreeFile()
        On Error GoTo DateiExists_DoesNot
        FileOpen(fn%, sDN, OpenMode.Input)
        FileClose(fn%)
        DateiExists = True
        GoTo DateiExists_Exit
 
DateiExists_DoesNot:
        DateiExists = False
        Resume DateiExists_Exit
 
DateiExists_Exit:
    End Function