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How do I reinstall Windows Defender to my Windows 7 Professional. It kept crashing, so I uninstalled it (And it DOES uninstall!) with the idea of reinstalling it.

But when I try to reinstall, the program insists that I already have it, and cancels the reinstall! It appears listed on my computer, but when I try to start it, the program says, correctly

Windows Defender does not exist as an installed service.

Nonetheless, when I try to reinstall, the install program insists that it will not install, on the grounds that the program is already there. But it is not. Is there any way I can reinstall it?

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See if it will install from this page

If you install MSE, it will disable Defender and take over the role it plays. Defender is an outdated product.

Be sure to uninstall any other Anti Virus you have installed Before installing MSE.

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Yeah, get MSE. It's 1000 better. – surfasb Jul 4 '11 at 6:15

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