Problem: Using Windows XP SP2 that is mapped to a DFS share will bluescreen when saving documents.
Recorded Microsoft KB artical: 906866 http://support.microsoft.com/kb/906866
Other related post: http://www.tech-archive.net/Archive/Windows/microsoft.public.windowsupdate/2007-04/msg00848.html
Fix: SP3 Fixes this problem, or you can follow the steps lisked in the two articals.