You did not mention which "popular anti virus software (free ones)" you've used.
Here are a couple of anti-malware programs that might help. If running them in normal mode does not work, try safemode.
(For Operating Systems: Microsoft
I'm getting this virus where every time I load up firefox I get new windows in IE poping up all the time randomly. If I leave my computer for 30 minutes I get about 50 popup windows all linked to various spam sites. I've tried popular anti virus software (free ones) and they all say that they can't remove the virus because it's currently being used. I think it's attached itself in one of the system drivers like netbios.sys
Does anyone know how to get rid of this? Should I just buy Norton anti-virus?

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