What do you get when you press those keys?
Does Task Manager open when you right-click on the Taskbar and select
Task Manager?
How about if you use Start - Run and enter TASKMGR in the dialog box?
There are some known viruses that can interfere with the operation of
Task Manager. The answers to the above questions will help to
determine if you may have one of these infesting your computer or if
the problem is caused by some other factor such as a registry change.
Good luck
Ron Martell Duncan B.C. Canada
--
Microsoft MVP
On-Line Help Computer Service
http://onlinehelp.bc.ca
In memory of a dear friend Alex Nichol MVP
http://aumha.org/alex.htm