If you keep an eye on the updates Windows installs, you may notice the Microsoft Malicious Software Removal Tool appearing every month. It removes some malware programs, but only a few -- it doesn't replace the need for an antivirus.



From MakeUseOf:

Microsoft’s malware removal tool exists as a sort of band-aid for the lack of antivirus in Windows. It attacks and removes prevalent malware, particularly worms, slowing their spread and preventing them from doing much more damage. It’s no substitute for an antivirus, which guards your system from a larger amount of threats, preventing them from taking root in the first place.

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