Windows Security

Fred Barnett 0 Reputation points
2026-09-15T14:55:42.9+00:00

After I uninstall Defender, how do I reinstall Defender?

[Tag moved from: Microsoft Security | Microsoft Defender | Microsoft Defender for Office 365]

Microsoft 365 and Office | Microsoft 365 Defender | For home | Windows
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  1. Norah-L 10,660 Reputation points Microsoft External Staff Moderator
    2026-09-16T06:24:37.8333333+00:00

    Hello Fred Barnett,

    If you removed the separate Microsoft Defender app included with Microsoft 365, you can reinstall it from the Microsoft Store. Open the Store, search for Microsoft Defender, select Install, and then open the app and sign in with the personal Microsoft account linked to your Microsoft 365 Personal or Family subscription.

    After signing in, follow the prompts to finish setting up protection and allow any requested permissions. If the Store shows Open instead of Install, the app is already installed, so you can open it directly from there.

    If you cannot find or install the app, make sure Windows is fully updated, restart the computer, and try the Microsoft Store again.

    Please feel free to post back if you encounter an error during the installation.

    Best regards.

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