Are you or have you been running any sort of anti-virus or anti-spyware program recently? If so which one. Spyware can sometimes mimick windows errors and if the fixes that people have sent you already are not working it may be an issue as simple as removing a piece of malware. Try a free scan to see if you have anything on your computer at
www.paretologic.com. Do not purchase the product, just do the free scan and let me know if it found anything besides the usualy minor threat cookies.
Cheers,