Shutdown dialog

[juacomoc]

Hello, I am having problems with the shutdown and restart dialog. I am using ubuntu 14.04 with Cinnamon.

It started some days ago, when I press shutdown, in the dialog that appears there is only the cancel button. So I shutdown the computer with "sudo shutdown -H now". Since today, doing that, the computer doesn't shutdown. The screen becomes frozen with the ubuntu logo. If I change to Unity, I can shutdown the computer normally. What can I do?

Thank you.