We have some XP machines and a mandatory profile on our Server 2008 standard.

All of a sudden we have students that can't log on to machines and a countdown timer appears which takes them back to the log on screen. If an administrator logs on and deletes the local documents and settings for that user then they can log on again fine. Once they log off, they can't log back on again though until an administrator has delete their local documents and settings again.

I presume it is a permission somewhere, but can't seem to find it.

Anyone got any advice or help?