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** Enable Task Manager from Registry in Windows 8, 7, XP or Vista
Registry Editor is an inbuilt Windows tool that is used to modify registry keys which tell Windows how it should work. A simple registry modification can be used to bypass the Task Manager block. To do so, just follow the steps:-
Click on Start. Go to Run. If you use Windows 8, Windows 7 or Windows Vista, go to Search.
Type regedit and press Enter. Registry Editor will start. If Registry Editor is also disabled, you will first need to enable registry editing.
Through the left hand navigation pane, navigate to HKEY_CURRENT_USER\Software\Microsoft\ Windows\ Current Version\Policies\System. If the System key is not there, you will need to create it.
In the work area, locate "DisableTaskMgr". If this value is not there, you will need to create a new DWORD value called DisableTaskMgr. Double click on it. A window will pop up.
Enter its value data as 0 and press OK.
Close Registry Editor. If Task Manager is still disabled, restart your computer.
**Enable Task Manager from the Group Policy Editor (Gpedit.msc)
enable task manager through group policy
Group Policy Editor is a feature in Windows which is used to edit local policy settings. It can also be used to enable Task Manager. To do so, just follow the steps given below:-
Open Start Menu. Windows XP users click on Run. Windows 8.1, Windows 8, Windows 7 and Vista users, go to Search.
Type gpedit.msc and press Enter. Group Policy Editor Window will show up.
From the navigational pane at the left hand side, go to: User Configuration>Administrative Templates>System>Ctrl+Alt+Del Options.
In the work area, double click on "Remove Task Manager" and set its value to Disabled or Not Configured.
Restart your Computer or Log Off and Log back On to apply the changes.
Group Policy Editor is not available on home editions of Windows.
**Enable Task Manager by Running a CMD Command
Command Prompt can also be used to directly enable Task Manager.
Open Notepad.
Copy the code given below and paste it.
REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableTaskMgr /t REG_DWORD /d /0 /f
Save the File as TaskManager.bat.
Run TaskManager.bat as Administrator if you use Windows 8, Windows 7 or Windows Vista. In Windows XP, simply open the file. A command prompt window will flash for a second and then disappear indicating successful execution. After running the batch file, you will be able to again use Task Manager. If Task Manager is still not available, restart your computer.
**Create a Registry(.reg) file for enabling Task Manager
If you are unfamiliar with manually editing the Registry, you can create a Registry file which will automatically modify the Registry Key to re-enable Task Managing. To create one such file:-
Open Notepad or any other text editor.
Copy the code given below and paste it as it is in it.
Windows Registry Editor Version 5.00 [HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System] “DisableTaskMgr” =dword:00000000
Save the file as Enable Task Manager.reg or *.reg.
Open the file by double clicking on it.
Registry Editor will ask you for confirmation. In the confirmation Window, click Yes.
Task Manager would immediately be accessible. If it is not, restart your computer.
*******If still not working then shut down your computer and restart it while booting press F8 button and enter the safe mode and then try one of the above methods