I know I'm kind of late to the party, but I'd like to add my two cents, anyway (since this may not only help the original poster deal with any similar issues in the future, but also potentially help anyone else, including anyone who finds this page via search engines).
For issues like this, I generally recommend doing a full malware scan using a bootable CD. Comodo has a bootable GNU/Linux-based rescue disk, which has served me well in the past. AVG also has a rescue disk (I believe theirs is also based on GNU/Linux, but I could be wrong) which has helped me on a few occasions, but I haven't used that in almost a decade, so I can't say for sure whether it's still any good (it could be abandonware for all I know). I'm sure there are plenty of other rescue disks available if you search around.
The reason I recommend a rescue disk, as opposed to installing an app, is simple: some malicious programs install system drivers, which are used to modify Windows system calls, which in turn allows malicious files to hide themselves from Windows programs (including anti-malware software). A rescue disk won't load said drivers, leaving this malware 100% exposed to the malware scanner, which in turn makes it easier for said scanner to remove said malware.