Do you have problems with your computer not shutting down when you power it off? You may need to make an edit to the registry to get the computer to power off when you select Shutdown. Try this:
Open your favorite registry editor.
Navigate to HKEY_CURRENT_USER\Control Panel\Desktop
In the right pane, double click the item named PowerOffActive.
In the value data box, give it a value of 1. Note that this should cause the power to go off at shutdown, but it only applies to the user account that's logged on when you make the change. If you want to make it apply to all users, substitute the following key in step 2: HKEY_USERS\.DEFAULT\Control Panel\Desktop.