Registry has been Disabled:-
Open RUN and type gpedit.msc
Now go to : User Configuration -> Administrative Templates -> System
In right-side pane, set Prevent access to Registry editing tools to Disabled.
Task Manager has been Disabled:-
Go to following keys one by one:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\Curr entVersion\Policies\System
HKEY_USERS\.default\Software\Microsoft\Windows\Cur rentVersion\Policies\System
HKEY_CURRENT_USER\Software\Microsoft\Windows\Curre ntVersion\Policies\System
In right-side pane, delete the DWORD value named DisableTaskMgr.
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