Hello,
It could be a big old nasty bug, but it ain't, so fear not, AtAF. A lot of programs are running when a computer is suddenly commanded to shut down. And sometimes some of those programs get caught before they can properly disengage. This is just a usual self-sustaining Windows process. You can go here to the following link to find out more:
http://www.overclock.net/t/1453560/windows-the-startup-and-shutdown-process
'I am a 
volunteer!
If it were a rattler. . . . Rattle Snake, that is. . . .