Fake antivirus software was the biggest cyber crime in 2010, according to security researchers. The bad guys have made this scam more effective and sinister. Fake AV shuts down your real antivirus and removes the icon from your system tray. It then shuts down any applications you have open, claiming that they may be infected. If you do get infected, there is actually a relatively easy way out. You have to reboot your system in safe mode (press the F8 key as you do) and then restore your system to an earlier recovery point.”]
Source: https://www.csoonline.com/article/2228663/nasty-fake-antivirus.html