Microsoft’s anti-malware program still isn’t very good

In spite of a recent effort to improve the performance and detection rates in Windows Defender, Microsoft’s anti-malware tool is still not very good at its job. According to the latest tests, it’s downright lousy. 

The latest round of tests performed by German institute AV-TEST, one of the most respected and regarded malware testing shops, show that Microsoft Security Essentials and Windows Malicious Software Removal Tool fared the poorest in removing an existing infection. 

AV-TEST conducted a lengthy, comprehensive test over a 12-month period to determine the best malware removal solutions for Windows 10. This involved 897 individual evaluations for each product, evaluating eight security suites. 

How AV-TEST evaluated the anti-malware tools 

The study consisted of two parts. First, the tools were installed on a system that was already affected. That’s an interesting test in and of itself because a lot of malware will actually block any attempted installation of an anti-malware product once the system is infected. 

Second, the suites were installed on a system but temporarily disabled in order to allow the malware infection to occur. Then the security software was reactivated. 

As AV-TEST noted, Microsoft Security could not deal with four malware samples that prevent cleanup, and it was the only security product that was blocked by malware infections: 

 “Eight times, Microsoft Security Essentials proved either totally or partially ineffective against the malware.” 

In the test of seven tools to clean up after a malware attack, the Windows Malicious Software Removal Tool failed to detect a total of 26 samples of malware out of 39 total and was not able to detect three active malware components. Of the 39 infections, Windows Malicious Software Removal Tool cleaned only seven of the systems completely. Its repair rate was 25.6 percent. Kaspersky Virus Removal Tool got all 39, and Bitdefender got 35. 

Among the eight security suites tested, Windows Malicious Software Removal Tool came in last with a 90 percent repair rate, with everyone else scoring 97 percent or higher. 

AV-TEST concluded that test suites are getting better, but it said nothing about Microsoft’s performance. It noted Avira Antivirus Pro, Kaspersky Internet Security 2016/2017, Malwarebytes Anti-Malware and Avast! Free Antivirus 2016 as the best performers.