A possible cause is malware that does this to make it more difficult to stop it. Try Process Monitor from Microsofts site sysinternals.com and see if that finds anything running that shouldn't.
Does task manager run if you boot into Safe Mode.
Kees
Hello. Im unable to access the task manager on a Dell inspiron e1405 laptop, running Wind XP. Ive tried the Cntrl/Alt/Del method and also from right clicking the task bar, but nothing will come up. Any ideas?

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