Answer:
In addition to updating your virus definition file, update the engine it runs on. I have found that this makes a difference, at least with McAfee. And remember that no system is fool proof. Anti-virus files are not produced until there is a virus. The best defense is an educated user. One important point here is to set your PC to view file extensions. In the "Kournikova" case a user would see the ".vbs" extension and know this was not a picture.
First published on BankersOnline.com 3/5/01