We have found on our client's PCs fake antivirus programs such as Personal AntiVirus and Windows Police Pro. These types of fake "anti-virus" or "anti-malware" are presented to the users throung browser ads, popup ads, or e-mails, tricking them to install the software "to fix your PC NOW!".

After installation, the software create the virus, offering to clean them up if the user purchases or upgrades the program.

The bottom line: review with your employees and users your antivirus software policies and train them with the basic securities best practices. Ensure they can determine if a popup is a real warning from the antivirus software or a fake ad, and what steps they must take if they suspect their PCs are infected with a virus and instruct them to not install software without permission.