Hi Abbeyhome,
Probably as process or application interfering. Before attempting a
shutdown, hit ctrl+shift+escape and make sure that no applications are
running. Then, on the processes tab, try killing off a handful (system
critical ones will not allow you to disable them, so don't panic). After
knocking off a few, try clicking the shutdown icon. If it works, then it
was one of the ones that you killed off that is causing the problem (so
you should make note of anything that you disable). If not, then it may be
on of the ones that is still running and you will have to try again. It
will likely take some trial and error to isolate the problematic one. Once
you know what it is, we may be able to find a solution for you.
--
Best of Luck,
Rick Rogers, aka "Nutcase" - Microsoft MVP
Windows help -
www.rickrogers.org