Microsoft Windows Defender

Contributor(s): Eddie Lockhart

Windows Defender is Microsoft's antimalware software. Defender works with Windows Update to automatically install new virus definition files as they are published and provide computers using the Microsoft operating system (OS) with both real-time and anytime scanning options.

Defender was originally released in 2006 as an add-on for Windows XP. With the release of Windows Vista, however, the software was enabled by default. Since the release of Windows 8, should a computer's default antivirus software be from a third-party and that software expire, Defender will automatically become the default AV once again. This is to ensure that every computer running a Microsoft operating system is using antivirus software.

Windows Defender is considered to be primarily a consumer-oriented security tool, geared toward the non-technical user who is not interested in purchasing additional protection. It does have the advantage of knowing the Windows OS better than any other tool and is quite good at removing malware when it is detected. Because it is a Microsoft product, however, it is also a target for malware designed specifically to attack and disable Defender.

This was last updated in March 2015

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What antimalware software do you use and why?
Most important to me is that you don't rely on one tool. Windows Defender is a good start, but after I scan with it, I turn it off and then use MalWareBytes, mainly because it's free, but also because it's proven effective in combination with MWD.
I use mult-layered defense against malware, because a long time ago, I discovered that nothing finds everything. I rely on the multiple layers to catch as much as possible. I discovered even though that with current definition tables Windows Defender does a poor job of protecting you. I give everything the benefit of the doubt, though, and that is why I went back to my layered defense.
I've been taught over the years that you shouldn't use more than one program for each Malware and an Anti-Virus Program? Doesn't running as many as you use cause problems?
I use 2 running all the time, Spybot Search and destroy and AVG. They both are free and I use Malwarebytes almost weekly as a catch all.