September 2009 was the month Microsoft released its completely free security solution for Windows users. It was called Microsoft Security Essentials (MSE) and won favor almost instantly with users through a combination of not costing anything to use, and actually doing a decent job of protecting your machine. It also helped that it works quietly in the background with no noticeable impact on system performance.Late last week Microsoft rolled out version 2.0 of MSE, and with it brought a number of improvements to give you even more peace of mind.AdChoices广告The first change is integration with the Windows Firewall. The only noticeable difference is that you can now update firewall settings from within MSE. Then there’s the updated heuristic scanning engine which no longer focuses just on anti-malware definitions. This should make it more capable at detecting new threats.Finally, there’s a network inspector which uses the Windows Filtering Platform to check as you browse giving an additional layer of security. This is also beneficial as it checks everything even if the firewall has been set to ignore something. However, one point that needs to be made about this feature is that it won’t work for Windows XP users, but the other updated features will.If you already use MSE, then don’t worry about upgrading as it will happen automatically. You’ll know when it does happen as it will probably trigger a system restart. If you don’t yet use it and want to try it, then visit the Microsoft Security Essentials website.Read more at Ars technicaMatthew’s OpinionI have been using MSE since it was released in 09, and I haven’t looked back. I first used it on a secondary machine, but when my paid-for license for Avira Antivir ran out on my main machine I switched. It does a very good job of keeping your machine secure, and uses very few resources.I should mention that I do combine it with a spyware package (SuperAntiSpyware) for complete peace of mind, but that may change depending on how much MSE 2.0 has improved.MSE has the advantage of always being free and no upgrade being available to a paid license. This is a feature of most other free security solutions which ultimately means regular reminders that upgrading would be a good idea. Why put up with that when MSE does a great job without them?