I have a PC that won't shutdown, but unlike most shutdown problems, this machine doesn't even begin the shutdown process. Regardless of how I try to initiate a shutdown, restart or even logoff, nothing happens: even the power button doesn't initiate a shutdown, using the task manager menus does nothing, selecting shutdown from the start menu brings up the 3 button shutdown dialog but nothing happens regardless of which button is pressed.
The PC has just been scanned with 4 different antispyware programs and 2 different antivirus programs. As far as I can tell it's clean.
I've disabled fast user switching.
I'm trying to decide whether a repair install is likely to help, or if I should start looking for a hardware problem.
Has anyone seen anything like this before?