I'm no techie but I know vista is notorious for needing permission and nearly everything I run has to be "run as administrator". Have you tried repair? Vista has the capability of repairing your files. These guys in here seem pretty smart so someone outta be able to help you figure it out, until then I would check permissions and maybe try repair.

http://onecare.live.com/standard/en-us/default.htm You can try this site and try the demo (as with anything, it's at your own risk). I've used it in the past when my pc started acting up. It checks alot of things with vista, including your registry.. But I cannot guarantee it'll fix your problem or help.. I never can with any program that "Fixes" problems but sometimes they work wonders!

I've had vista for about a year now.. It's a bugger but it's getting better, slowly. lol

Best to you!
xts
PS. Please note: The link above is not an advertisement, it's a reference link.