"You'll need a new app to open this windowsdefender link" fix

The following path applies to Windows 10 only.

C:\Windows\SystemApps\Microsoft.Windows.SecHealthUI_cw5n1h2txyewy

SecHealthUI package is stored in a different folder on Windows 11. For Windows 11, you use the following command:

add-appxpackage -disabledevelopmentmode -register ((Get-AppxPackage Microsoft.SecHealthUI -allusers).InstallLocation + '\AppxManifest.xml')

Hi this post is to help people with windows 10 and 11 windows security not working

On windows 11 do this

1. launch powershell as an admin
2. Set-ExecutionPolicy Unrestricted
3. Get-AppXPackage -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml"}
4. Set-ExecutionPolicy restricted

IGNORE THE ERRORS

on windows 10 do this

1. launch powershell as an admin}
2. run get-AppxPackage Microsoft.SecHealthUI -AllUsers | Reset-AppxPackage
3. if it doesn't work do this
   4) run Add-AppxPackage -Register -DisableDevelopmentMode "C:\Windows\SystemApps\Microsoft.Windows.SecHealthUI_cw5n1h2txyewy\AppXManifest.xml"
4. run get-AppxPackage Microsoft.SecHealthUI -AllUsers | Reset-AppxPackage

Does the Windows 11 PowerShell command ignore the errors or actually resolve the issue? I'm running Windows 11 and seem to be missing the C:\Windows\SystemApps\Microsoft.Windows.SecHealthUI_cw5n1h2txyewy\AppXManifest.xml folder / file that I believe Windows Security relies on. So would this restore that folder / file?

it works !

Very Good

Thank You so much! It worked. ^_^