I eventually downloaded something called Giant Anti spyware - it found and removed LOADS including the Bullseye network offer one - to see if you have got any spyware go to Add/Remove programs and look for 180search assistant, WinAD client, Bullseye network offer, Bargains.exe and other weird programes. They aren't viruses as such but they give you lots of annoying popups and can change your internet settings.
Giant anti spyware removal Trial
HTH