set filesystem = CreateObject("Scripting.FileSystemObject")
set file = filesystem.OpenTextFile("C:\Autoexec.bat")

Do while NOT (file.EndOfStream)
MsgBox(file.ReadLine)
Loop

set newfile = filesystem.OpenTextFile("C:\testme.txt")
newfile.WriteLine("VBScript schreibt Dateien...")
newfile.Close

set appendfile = filesystem.OpenTextFile("C:\testme.txt",ForAppending)
appendfile.WriteLine("This text is appended...")
appendfile.close