PC won't Shut down

[wonder.]

I have a retail system builder edition version of Windows Vista Ultimate and after I moved my computer back upstairs and put it on my new desk, when ever I go to shut it down, It goes to the shut down screen, says its shutting down but never actually does.  It just stays there.  Any Ideas?  I heard MDK say it might be cause im running a program thats not letting it shut down, but I checked and thats not the case.  Where my computer is, is alittle cramped, could it be its getting hot so it won't shut down till it gets cooler?  I have to hold the power down to shut off my comp, and I really don't like doing that cause its not good for it.  Any Ideas?

Thanks

~Wonder.

[DEATHHAVEN]

go thru the task manager and shut down each process in order one at a time until the machine will shut down on its own and when you find the one where it shuts down uninstall and reinstall the program

[GeoDragon30]

If it locks up at the end of the shut down and just doesn't power off i have found registry errors that have happened and fixed them and that fixed my problem.

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