Are you using MSE?
You can run a Full Scan in SafeMode using MSE to remove all possible threats.
If you are not using MSE you can run an Online Scan through SafeMode with Networking.
Use this link for the Safety Scanner:
http://safety.live.comRun the Protection scan then use the Complete Scan.
If that doesn't help you can submit a support case:
https://support.microsoftsecurityessentials.com/Then choose "I think my computer is infected", follow the process in obtaining support.
MVP [2010] | Consumer Security
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