When i turn my computer on this message appears:
"Logon has caused an error in <unknown>
Logon will now close

If you experience problems,
try restarting your computer."

Then the screen freezes and I can't do anything but switch it off at the plug.
Is my computer dead??? :confused:

Did u terminate the Service,winlogon.exe?if yes,your system cannot log0n!

It sounds to me like you need to do a restore of XP (http://www.techspot.com/vb/topic8356.html) Give this thread a look and see if that works. Once this is done, make sure you run Windows Update as it will get rid of all of your updates.

BTW
:wave:Welcome to TechSpot:wave: