Microsoft Defender aces this one, earning AAA certification. London-based SE Labs (Opens in a new window) awards five levels of certification, AAA, AA, A, B, and C.

Several other products likewise earn a perfect score in the latest test, among them Avast, AVG, and Kaspersky Security Cloud Free. In the latest report, Defender takes the full six points in all three categories, for a perfect 18 points. An antivirus can earn up to six points for each of these, for a maximum total of 18. Security experts at AV-Test Institute (Opens in a new window) rate antivirus programs on three criteria, Protection, Performance, and Usability. Its scores run the gamut from perfection to failure.

At present, all four of the labs that I follow include Microsoft Defender in their regular test reports. Some years ago, Windows Defender (as it was then called) routinely earned truly rotten scores from the independent testing labs, coming in below zero at times. Most competing products make scheduling scans much easier. If you want to schedule a scan, you'll have to dig into the unwieldy, threatening Task Scheduler app. You won't find that functionality in Microsoft Defender, though. However, many users like to schedule an occasional full scan for added security. It's true that after that initial full scan, real-time protection should handle any new attacks. (Opens in a new window) Read Our Check Point ZoneAlarm Free Antivirus NextGen Review How to Set Up Two-Factor Authentication.How to Record the Screen on Your Windows PC or Mac.How to Convert YouTube Videos to MP3 Files.How to Save Money on Your Cell Phone Bill.

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Is microsoft antivirus good