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I am using a Compaq Presario C700. Before upgrading from Ubuntu 12.10 everything was fine, but since I switched to Ubuntu 13.04, I can't shutdown my system in any way. The only thing I could do is hold the power button until it shuts down on its own.
I have tried using the terminal to shutdown, but it's no use. When I click on the shutdown button on the title bar, there is no option for shutdown. The only thing I could see is Lock Screen and Log Out. What should I do?