AntiVir Free Antiviurs is one of the best free antivirus programs and the one I have chosen to use. One of the problems of the popular antivirus programs like Norton and Macafee is that they are now being directly targeted by viruses and disabled leaving the computer unprotected. Another problem is that those popular ones are becoming bloated as they try to do everything for your computer so they wind up slowing you down. The best thing to have is a light program like AntiVir that does it's job against viruses without slowing you down.