Many a times when we press Alt+Ctrl+DEL computer users face this below proble When you try to run Task Manager, you receive the message that Task Manager has been disabled by the Administrator‟. And the error message seems funny You logged in using the Administrator account and still this error message Strange you don‘t know how this has happened. The strange thing is that it is on the Administrator user identity that you get this problem.
This all happens due to some malware or spyware software putting some registry restrictions so that one can‘t trace or remove them from the system startup and you can enable your Task Manager by Registry Editor and by Group policy I enable my computer task manager by these methods many time so please try this I think it will help you
1. Click Start, Run and type Regedit.exe
2. Navigate to the following branch: HKEY_CURRENT_USER\Software\ Microsoft\Windows\CurrentVersion\Policies\System
3. In the right-pane, Disable the value named DisableTaskMgr
4. Close Regedit.exe
Using Group Policy Editor - for Windows XP Professional
1. Click Start, Run, type gpedit.msc and click OK.
2. Navigate to this branch: User Configuration/Administrative Templates/System/Ctrl+Alt+Delete Options/Remove Task Manager
3. Double-click the Remove Task Manager option.
4. Set the policy to Not Configured.
100% Working methods…!!
Be carefull when you are working in Registry Editor