Very small sample size. Platform used again is WIN 7: The sample set comprised 100 actively-malicious URLs and 100 legitimate applications and URLs. This might account for MSE's higher scoring. More so if these were prevalent malware. Microsoft has already publicly stated that MSE's protection specifically targets those. I will stick with the larger AV labs more comprehensive tests that always show MSE at the bottom of the heap. Still waiting for Windows Defender tests on WIN 10. PC Mag doesn't think it's all that great.
To be fair Microsoft is doing right, prevalent malware protection is much more important to the average user. In these more comprehensive tests we see many antivirus doing 99 ~100 % protection in real world test and yet many users are infected each day.
MSE is performing almost the same at the other labs. DTL: 94% AV-C: August: 92.8% AV-C: September: 93.1% AV-T: July 91% AV-T: August 87%
Actually A-V Comparatives did test Windows Defender on WIN 10 in its latest file detection test. It scored the lowest of all products tested. So nothing has changed overall other than it is at least scoring in the low 90% range now.
"Editor's Note: It turns out that the poor performance of Microsoft's Enterprise-level product was caused by a configuration error that deprived the antivirus of access to its cloud database."