I used to have Avira Antivir. Then I got a rogue antispyware virus. I tried removing twice with Antivir (and Spyware Doctor) and it would not go away. Then i got Windows Live OneCare, ran a scan with it, and the virus was gone. I had no more popups. This just goes to show that you get what you pay for. Usually if you use a free Antivirus, then it will not work nearly as well as an antivirus that you pay for (except for Norton, Norton is just a piece of junk).