A Security Analyst working at ParetoLogic feels thats Microsoft Security Essentials is better than a lot of paid AntiVirus products.
Take this pretty common Trojan from fastdor.ru/video/preview_tube.mpeg.exe
Well, only a handful of AV vendors are detecting it. A lot of the big guys don’t detect anything at all! Microsoft picks it up without a problem.
MSE’s main install only takes 11 MB out of your hard drive and t’s DB remains small as well. There are 2 main files for the full DB. mpasbase.vdm (anti-spyware) and mpavbase.vdm (anti-virus) which are respectively just 9 and 29 MB.

“What is Microsoft’s secret recipe for being so good? What kind of detection are they using that they can maintain such small Databases? I wanna know” says Jerome Segura.
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