I have always found Trend Micro Titanium Internet Security 2012 to be very effective in removing these types of threats. The good thing about this is they give you a free trial that is fully functional that will remove the threats if you just need to resolve the issue. After my stress with getting rid of a trojan that not of the other programs were able to clean, I installed Trend and never looked back since. No regrets.
Another option is to download and use their housecall program to assist in removing the pest.
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