MS has released an update that cleans up user profile leftover files and processes and helps to ensure user sessions are completely terminated when a user logs off.

Processes and Applications can occasionally maintain connections to registry keys in the user profile after a user has logged off.   In those cases the user session is prevented from completely ending.

This can result in problems when using Roaming User Profiles in a server environment or when using locked profiles as implemented through the Shared Computer Toolkit for Windows XP

For more information and/or to download this update: http://www.microsoft.com/downloads/details.aspx?FamilyID=1b286e6d-8912-4e18-b570-42470e2f3582&DisplayLang=en