Can't open registry editor or task manager?

If you aren't able to open your registry editor or task manager even though you are the administrator then you have got a problem.
Probably you have a virus or a malware attack. Now better to scan and find the infected files and stuff.
But even after doing a check up you still can't solve the problem then following are some registry solutions.

If you can't open the registry editor then go to START->RUN and paste the following command:

REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableRegistryTools /t REG_DWORD /d 0 /f

Hopefully this should solve the problem.

For enabling the task manager:

REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableTaskMgr /t REG_DWORD /d 0 /f

Hope this solves your problem.