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

This is the exact problem I'm having. My main admin account is fine, never had a single issue.

My secondary accounts (wife and child sub accounts with no admin access) have the same problem. There's an exclamation point on the Windows Security shield stating that Action needs addressed. I can't get rid of it. I can't open Microsoft Security. Everything is patched / up to date, but I'm unable to run scans.

like a magic dude...great :)

thx

thank you fixed me right up

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

I was having this problem on Windows 11 after I upgraded from Windows 10. I followed the direction for fixing the problem on Windows 11 using PowerShell as an administrator and this procedure did resolve my problem ever thing is working fine now.

This worked liked a charm for me after trying for several days. Windows defender, windows security center, and few other apps came magically back after following TrippCollins advice. I think I caused the issue trying to delete bloatware and messing with the wrong program. Thank You sir! This computer is a month old.