Conficker alert poping up every now and then

At random times a warning message about a Win32.Conficker pops up and every time I choose to disinfect, but it won’t stop. This started happening today, I never had this problem before. Also, I don’t visit suspicious websites. Help?

EDIT: A screenshot.

One does not always need to visit dodgy sites to get infected. Also regular sites can get infected. Using cracks could get you infected as well…

Please follow What to do if you’re infected - eXPerience Rev.3 and report back.