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Now, there is also a new Windows Defender for Windows 8 that you don’t need to install, because it comes built-in with the operating system.
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One thing to keep in mind is that they do not play well together, to avoid problems by default “Security Essentials” disables “Defender” during install. However, sometimes MSE doesn’t automatically disable Windows Defender, in this case you’ll need to manually do this task or perform an uninstall, because both software running together can cause PC performance issues and conflicts between the two services. The software giant designed MSE as a Windows real-time protection, and it does a really great job detecting and removing viruses, Trojans, rootkits, worms or malware, and spyware for its price ($0).
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Microsoft Security Essentials (a.k.a MSE) for the same line of operating systems is a more complete AV solution.
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