Windows 11 – Fix Missing Defender / Windows Security

I’ve recently encountered an issue on Windows 11 devices whereby Windows Defender and the Security portal refuse to open, with it showing a “You’ll need a new app to open this windowsdefender link” popup. This appears to stem from a corrupt app install after one of the recent patches.

The Solution

The solution requires that PowerShell be ran as an administrator. Run the following commands one at a time and test access to Defender / the Security portal after each command.

Get-AppxPackage Microsoft.SecHealthUI -AllUsers | Reset-AppxPackage # Attempt to fix the Security Health UI App

Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register “$($_.InstallLocation)\AppXManifest.xml”} # Disable development mode of all Apps which should resolve the issue

3 thoughts on “Windows 11 – Fix Missing Defender / Windows Security

  1. Hi Shaun
    Thanks for the tip on how to solve the problem. Have been looking for a long time if anyone had a solution.
    The first line did not solve the problem but the second line solved it.

    So a big thank you.

    // Stefan Sandberg

    Like

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