Hi,
A few questions that you might want to ask yourself:
When did this start to happen? What changes did you do that might have cause this issue?
If you know when it started, a simple way is to do a system restore, and install one update at a time and test out which update is causing the issue; and if you know what changes caused this problem, please uninstall the update and wait for the next revised
update (or, install ALL avail updates from Windows Update).
Jabez Gan [MVP] - http://www.msblog.org Contributing Author for: (Sybex) MCTS: Windows Server 2008 Applications Infrastructure Configuration Study Guide: Exam 70-643