I'm not able to power off Ubuntu, which was working fine a couple of days ago. When I click shut down, a blank screen appears and stays like that forever. It does not power off by itself and I'm forced to physically power off using the power button.
I've even tried 'sudo shutdown now' and 'sudo shutdown -h now' and both don't seem to work!
Please suggest some fix for this problem.
Thanx in advance.
Edit: Restart works fine. Also 'sudo poweroff' doesn't work!