How did I get a virus when I have a reputable anti-virus program?

This is a very valid question, and the reality is 98% of customers that call in with a virus have a good anti-virus program running, and the infection simply disabled the anti-virus program and began launching popups and blocking your Internet browsing. Anti-virus vendors, including the big names like Symantec and McAfee, are having difficulty keeping up with all the new malware that comes out on a daily basis. The anti-virus vendors are about 97% effective at stopping the 3000 new pieces of malware that come out per day, but typically 3% of malware will completely bypass your anti-virus software.