Microsoft Security Essentials
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Full user review
"Free and Fast"
-Uses little resources
-Has quarantine and sets restore points
-Not as effective as Avast
I was using Avast but the newer versions have become bloated and it slows my PC when browsing, I know Avast is more thorough than MSE but I don't visit questionable websites and use torrent. MSE uses very little resources so you hardly notice it when browsing, it also scans your PC fast. Version 2.1 is better than the first version I tried back in 2009, it has quarantine and it scans faster.