A reader recently asked us if she needed Windows Defender, antispyware software from Microsoft that comes with Windows Vista and Windows 7, if she had downloaded Microsoft Security Essentials (free antivirus and antispyware software).
If you use Microsoft Security Essentials, you don’t need Windows Defender. When you download Microsoft Security Essentials, it will turn off (but not uninstall) Windows Defender automatically. It does this so that you don’t have two programs on your computer that are doing the same thing. If you ever decided to uninstall Microsoft Security Essentials, Windows Defender will be turned back on again.
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