Once connected, cyber criminals stealthily install malware and/or change system settings. In addition, these people often trick users into granting remote access to their computers. In fact, cyber criminals claim to be certified technicians and attempt to monetize their services that are not needed. This error is fake and has nothing to do with Apple. Bear in mind, however, that 'WARNING! MAC OS Is Infected' is a scam. Certified technicians then supposedly guide users through the malware removal process. Users are advised that they must not hesitate to call Apple technical support via the telephone number (' 1-84') provided. This error states that the system has been infected and that the malware must be removed and system repaired immediately. These programs also deliver various 'malvertising' ads (pop-ups, banners, coupons, etc.), record information (mostly, about web browsing habits), and misuse system resources.
This error is displayed by a malicious website that users often visit inadvertently - they are redirected by various potentially unwanted programs (PUPs). 'WARNING! MAC OS Is Infected' is a fake error similar to Apple Security Alert, Apple Support Center - Attention!!, Apple Warning Alert, and many others. How to remove WARNING! MAC OS Is Infected from Mac?