My computer's task manager stops working

Ethiopia
March 3, 2008 5:20am CST
My computer's task manger icon is not active .How can I make to be normal.When I click 'ctrl+alt+del' the other buttens like 'cancel','change password','log off' are active except 'task manager'.My AVG antivirus is working normal and it updates every day.Please any body who has idea on this .Share me as soon as possible
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