Windows Defender won't open? Here's how to fix it! (Windows 11)

Anonymous
2022-02-17T05:36:47+00:00

Last edited: 23/4/2024

[PLEASE NOTE BEFORE READING]

This fix is more than 2 years old. There is a high likelihood that it may not work on your system.

BEFORE YOU COMMENT, "It doesn't work" or "Not working," PLEASE REMEMBER! There are actual users looking in the replies for other solutions as well. If it does not work for you, please also include the errors that you encountered and which step you got stuck on. This way also gives me a chance to possibly help you.

If you can't or do not want to include more information on not being able to proceed with this fix, simply move on and try other fixes.

=================

Remember: Make sure you are using an administrator account, are the owner of the device, or have permission from the administrator to proceed with these steps.

Windows 11 is a brand new OS. Windows Security may not be opening, as many users have said. The following steps may fix this issue for you:

Step 1: In search, type "PowerShell"

Step 2 As PowerShell appears, press "Run as Administrator" Click "Yes" on the following prompt.

Step 3: Enter the following commands separately in order shown.

1. Set-ExecutionPolicy Unrestricted

(If it prompts you with (Y/N) which is "Yes or No", type Y. If not, proceed to the next step)

2. Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register “$($_.InstallLocation)\AppXManifest.xml”}

Added by mod (ty): Revert execution policy.

3. Set-ExecutionPolicy Restricted

Try opening Windows Security after. It should now work. Feel free to post any other solutions and questions.

EDIT:

This second option will work even if you are not an administrator:

https://techcommunity.microsoft.com/t5/windows-insider-program/issue-with-windows-defender-on-windows-11/m-p/3261866/highlight/true#M15320

Link suggested by hiThereSomeUserHere.

Suggested by Amirali Hendi:

Download the Windows Security App from the Microsoft website. The link: https://www.microsoft.com/en-us/microsoft-365/microsoft-defender-for-individuals

launch it and log in to your Microsoft account. Then close it. Now you can launch the Windows Security app!

(I am not a Microsoft official, so I cannot promise that this will not harm your computer. Make sure you have permission from the administrator before doing this.)

Windows for home | Windows 11 | Security and privacy

Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.

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  1. Anonymous
    2024-02-22T20:43:24+00:00

    I just tried this and it did not work what so ever.

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    2 people found this answer helpful.
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  2. Anonymous
    2024-02-15T17:46:55+00:00

    I get

    Get-AppXPackage-AllUsers : The term 'Get-AppXPackage-AllUsers' is not recognized as the name of a cmdlet, function,

    script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is

    correct and try again.

    At line:1 char:1

    • Get-AppXPackage-AllUsers |Foreach {Add-AppXPackage -DisableDevelopmen ... 
    • 
    + CategoryInfo          : ObjectNotFound: (Get-AppXPackage-AllUsers:String) [], CommandNotFoundException 

    + FullyQualifiedErrorId : CommandNotFoundException

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    2 people found this answer helpful.
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  3. Anonymous
    2024-01-21T05:13:41+00:00

    https://winhelponline.com/apps/Microsoft.SecHealthUI_8wekyb3d8bbwe.appx
    is     another fix to reinstall the Windows security app with an older version to be able to use it until a bug fix comes out.

    OMG, This actually worked!! Thank you so much!! I was about to reset computer for a THIRD time (URGH), and decided to find this last, i.e., most current solution, and DAMNED if it didn't work.

    Prior to this, Defender did not open at all, none of the "Protected areas" windows opened--they were blank.

    One thing I did do when I got to the "Windows Security is already installed" window is, I Reinstalled it, and then launched it. Before reinstalling, the Launch brought up nothing.

    I've been working on this for days and I am already a help desk tech person. If I had this much trouble, other people must be launching their computers out their actual windows. MICROSOFT should be ashamed for letting it get to this point. Either pay YOU for your solution, which would be my first recommendation, or get the hell on the ball and fix this ridiculous problem with Defender in Windows 11.

    Should probably preface this with the fact that I ran the solution provided by Skorper, using PowerShell, as directed, at the beginning of this conversation, see above.

    You're a genius! Seriously. Thank you so much.

    Oh, one last thing. Notice that the "is" right below the hyperlink above is include as part of the hyperlink. It's important to copy the full hyperlink and stop before the "is" or it gets included and then the link doesn't work.

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  4. Anonymous
    2022-04-09T10:09:09+00:00

    Hi

    Thanks for tis fix. It worked fine for me

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  5. Anonymous
    2022-04-08T23:22:12+00:00

    Thank It Work For Me!!

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