Windows 7: Windows Secuity Center keeps disabling itself

Well,I have recently downloaded a keygen that seemd to have a trojan...Since then my security center is always off.First I have went to the services where I had a problem,it was something like ActiveX isn't working,that thing didn't let me open the services,I have ran some anti spyware and malware programs and i have managed to open the services.I have set the Security Center to Automatic and started it.After like 10-20 seconds it hase disabled itself.I kept setting it to automatic and it kept disabling itself...Please help me....

P.S.:I have scanned the computer several times with Nod32,still,it didn't find anything.

Have you tried system restore?

unfortunateley,system restore was turned off for me and so i have no restore point...

wont you try to rescan your PC with hitman pro and malwarebytes to see if it catches something.

doesn't that affect my current nod32?

No. They're on-demand scanners, unless your purchase the full version.Go ahead and scan with the two.

and what do u guys mean by "something"? trojan or such?

That would be the cause of your troubles

That 'something' includes all malware.

Have u done the scans with MBAM and Hitman Pro?

no,never,i have no idea what "malware" means....

sorry for the "no,never",i thought u ment something else...