Hi Leander,
Please understand we discuss Windows Vista issues in English in this forum. If you write in English or your operating system is in English, we are not the best resource to troubleshoot your issue. I suggest discussing the issue in our German public newsgroup. Thank you for your understanding.
http://www.microsoft.com/germany/community/server/newsgroups.mspx
You can also contact Microsoft Germany Customer Service for direct assistance:
http://www.microsoft.com/worldwide/phone/contact.aspx?country=Germany
I hope your issue can be resolved soon.
Tim Quan - MSFT
