How do I get rid of XP Security 2011?

This past weekend I had the misfortune of having XP Security 2011 loading itself on to my computer. I utilized Webroot Internet Security  Essentials which did not resolve the problem. I used Norton Antivirius 2011 which did not detect it either so I used Norton Eraser which did spot it but prevented me from using applications is a normal manner.

 

What Antivirius program can resolve this problem ?