vista invalid product key

Hi ya'll, after a year of working fine, my mom started getting an error message on her laptop (Toshiba Satellite L305 s5885) that windows vista home premium was not a genuine copy. It is now only giving three options: Reduced functionality(I'm using this now, no desktop, only access to ie), enter a different product key and contact dell.

I entered and reentered the product key on the bottom of the laptop with no luck, then I called Microsoft and they gave me a new product key which still didn't work. They suggested that it might be a bad or generic driver.

I can't download any updates or fixes from Microsoft(I get an error message that it doesn't apply).

I finally reset it to factory through sysprep thinking it would reset the drivers or whatever and it went through all the set up and I'll be damned if I didn't end up with the same three options and an "invalid" message.

I have no access to the start menu in regular mode, but I can get to command prompt throught ie. I've tried slui.exe 4 and 3, registry cleaner(Microsoft also suggested a corrupted registry could be the issue), malwarebytes, spybot, ttskiller....nothing detected.


At this point, I'm exausted. This started about a year ago and I got frustrated and threw it in the closet...she has since replaced it and I only started messing with it again out of sheer boredom but now it's making me nuts.

Any help would be greatly appreciated!

-Katie