"Viruses Detected" Pop-ups
"Viruses Detected" is the name given to a fake error message that you may see on your Windows system. While you are browsing online, you may suddenly see scary pop-ups containing disturbing error messages about your computer being infected with viruses.
The full text of the fake error message reads as follows:
Viruses detected (X)
Your computer is infected with dangerous viruses
Click "remove viruses" and remove all viruses.
Viruses detected (X). Click to remove viruses.
The number of fake detections may vary and will usually be a relatively tame number under 10, but still enough to scare the user into action, because who would want 7 viruses on their Windows PC.
The catch is, the message is fake. The fake virus detection pop-ups may also use Windows branding and the Windows logo to trick the user into thinking the detection and message originate from Microsoft or the operating system.
The reason you might be seeing those fake virus detection messages is either that you have adware on your system or that you hit a web page redirect that led you to a site that displays those fake messages.
Fake virus detection messages of this type are commonly used to mislead users and get them to install rogue anti-malware applications or other malware. The simple social engineering trick used by the bad actors in this specific case is scaring the victim into action. A scared user might click the button to remove the non-existent viruses impulsively and cause further damage to their system in the process.
Bear in mind that Microsoft and your Windows OS will never show you any virus or malware notifications that did not originate from the native Windows Defender application and will certainly not show you any virus detection messages in a browser window. Stay away from those fake messages when you see them and close the browser tabs or pop-up windows that show those messages immediately, then, if possible, run a malware scan of your entire system.