How to enable Task Manager in Windows ?

From the Group Policy Editor (Gpedit.msc)

Group Policy Editor is basically used to edit local policy settings. It can be used to enable Task Manager. 

Follow the steps given below :

=> Open Start Menu

=> Type Run and press Enter

=> Type gpedit.msc and press Enter. This will open Group Policy Editor

=> Now navigate to
 User Configuration < Administrative Templates < System < Ctrl+Alt+Del

=> Double click on "Remove Task Manager" and set the value to Disabled or Not Configured

=> Restart your Computer to apply the changes you just made.

From Registry Editor (regedit)

Registry Editor a tool used to modify registry keys.

Follow the steps below :

=> Click on Start. 

=> Type Run and press Enter

=> Type regedit and press Enter. Registry Editor will open

=> 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.

=> Choose "DisableTaskMgr". 

If it is not there, you will need to create a new DWORD value called DisableTaskMgr. 

=> Double click on it which will open a new window

=> Enter its value data as 0 and press OK.

=> Close Registry Editor and restart your computer to affect the changes

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