we have a problem with users who has roaming profiles. When user is going to log on it looks like the user dont have rights to her profiles any longer and the administrator has to log on and take the ownership of the documents and give back the rights to the user. Is that anything you recoginze.
It sounds like the roaming profile has become corrupted on the local machine. Could be be a virus or malware. Try to run a command line Scan on the machine. Download win_betaengdat.zip from the threat center http://vil.nai.com/vil/virus-4d.aspx. Run this command in safemode at the command prompt scan.exe /clean /adl /all /program /unzip /rptall /report=c:\scan.log This could take a couple of days if this doesn't work. Then I would need to backup up mydocuments, Favorites, Outlook history and remove the profile and create it again.
Hope this helps