A thing that is popping up trying to get me to buy(Antivermis)went into cont. panel &removed~didn't work~HELP

This program is a box flashing on my icons on the bottom right and keeps popping up saying "system alert". When I log on and try to go to yahoo.....it pops up...protectionsoft.com. I went into the control panel and tried to remove ....it's not showing up there, but this junk is still there. How can I remove it from my icons? and computer?