A. MSE is Microsoft's new antivirus/antispyware offering for basic desktop use. It's provided free of charge. MSE is a replacement for the subscription-based OneCare service, but MSE will only provide antivirus protection, not OneCare's other features such as backup management, wireless network management, and optimization.
MSE, shown here, supports Windows 7, Windows Vista, and Windows XP SP2 and above. MSE can't be used on server OSs and your OS must be genuine to install and use MSE.
MSE is a very thin antivirus solution and uses less of your system resources than OneCare.
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