There are numerous reports of people “verifying” their copy of Windows, so one can download Windows Anti-Spyware, only to be told they have an invalid copy of Windows.
This may not be the fault of the vendor/system builder.
Until Microsoft sort this out you can download a copy from BetaNews
The Microsoft site also gives you the option to bypass Windows Verification by selecting the "No, do not validate Windows at this time, but take me to the download" option when you get to the verification page.....
the software it self is pretty neat! Except Microsoft will prompt you to validate windows etc.. For some reason they could not validate my operating system, so I had to pull out serial # all the way from the bottom of my computer...
If you've tried all of those without success then it looks like you've got a nasty bit of stubborn Spyware on there.
One way to have a look is to use a useful little tool called HighjackThis - it examines certain key areas of the Registry and Hard Drive and lists their contents - you can then copy and paste it into a forum thread so others can have a look and identify what nasty little bug is lurking and help you remove it.
You can find it at http://www.tomcoyote.org/hjt/ - have a look and give it a go - if you dont want to put it on here - PM me and I'll have a look....