Schon macht man es richtig funktioniert es !

Private Function GetBytes(filename As String, 
        position As Integer, length As Integer) As Byte()
 
    If position < 0 Or length < 1 Then
       Throw New ArgumentException("Invalid Parameters")
    End If
 
    Dim bytes(length - 1) As Byte
 
    Using fs As New IO.FileStream(filename, IO.FileMode.Open, _
      IO.FileAccess.Read)
        If position + length - 1 > fs.Length Then
           Throw New ArgumentException("File too short")
        End If
        fs.Position = position
 
        fs.Read(bytes, 0, length)
    End Using
 
    Return bytes
End Function

 Dim fi As New IO.FileInfo("G:\Clips\Dokument.txt")
 Dim position As Integer = CInt(fi.Length) - 128
 
 Dim byt() As Byte = GetBytes("G:\Clips\dokument.txt", position, 128)

Schon macht man es richtig funktioniert es !