I have this very weird problem: When I want to open the Task Manager (ctrl+alt+del), XP tells me that "Task Manager has been disabled by your administrator", if I click OK, or the red cross, the computer reboots. I have tried to scan the computer several times with various anti-virus programs, and scanned the registry but that didn't help...
By the way I am the administrator, and only user!
Please Help anyone, I am going insane!

Hi Raphael,

Welcome to PCHF. Can you check out PCHF Prework on my signature, and post an AVG and Hijack this log back here so that one of our security team can see if your problems are related to malware?

In the meantime, can you also try creating and testing a new user account. Go to Control Panel, User Accounts and create a new account from there. Go to Start and Log Off to take you back to the Welcome screen, and then try and logon with your new account. Does your problems still exist with this new account?