So here's what happened. I started up my PC which I run windows 7 on. I bought windows 7 fair and square. I have the physical box and everything to prove it. After about 5-6 months of using it, my PC just started up claiming that this copy of windows is not genuine. After a while, it seemed to go away after I clicked "ok" on a few bits of text I didn't read. I ran slui.exe, it said that the genuine check was successful...
so what the hell happened there?
Check under Control panel > System and security > System, at the bottom of the window it should say if Win is activated.
Well most probably trojan/virus. Something messing with the registry. I think you should start from there (unless googling didn't give any useful results).
Download Spybot, Malwarebyte, Bitdefender, Avira (all have free versions or are free), run them one by one (shut down other antivirus software so they won't kill each other), be careful with spybot, so you don't delete something important.
Anf before that, transfer important stuff (documents etc.) on a disk or partition different than where Windows are installed.
Good luck.
p.s. you bought it, bother tech support, that's what they're there for and you have the right to molest them. ;D
I think that third-party software, changes to your hardware, of microsoft's servers being temporarily unreachable can all cause your installed version to register as "illegal".
Hm. I scanned, nothing.
Thanks for the tips, I guess it might have just been a temporary disconnection.
If you change the configuration of your hardware to such an extent that it is very different from the original configuration, Windows may flag itself as non-genuine as it uses hardware profiling.
Also for Windows 7, the way to tell if you have a genuine 'Non-genuine' error, you will have this in the bottom corner of the screen:
(http://media.wiley.com/Lux/32/146732.image0.jpg)
If not, then it will be some kind of malware.