My computer will not shut down

You might be experiencing a blue screen when shutting down. It might be appearing and disappearing too quickly for you to notice. Also windows could be set to restart by default on a blue screen or similar error.

You can disable this by going to Control Panel, System. Go to the Advanced tab and click on the settings button in the Startup and Recovery section. In the System Failure section uncheck Automatically restart. This will stop the computer from restarting at the blue screen, allowing you to take down the details of the error.