Cannot Access Windows Defender

Question

Hello all. I upgraded to the Windows 11 Preview this morning, and I discovered a little while ago that I can't access Windows Defender, or any security setting for that matter. When I click open security settings, I get an error box stating, "you'll need a new app to open this windowsdefender link" and I'm prompted to go to the Microsoft Store. Everything is up to date. Before the jump to Windows 11 preview, I did reset my computer at the prompting of an agent, because I kept running into a blue error screen while installing the update. I reset and downloaded Windows from the cloud rather than my device, as I thought that could have been an issue. Could that have possibly have been it?

Answer 1

Hello,

Same thing happening to me. It has been seen elsewhere On the Windows Insiders Page. Windows 11/Defender

Ok. Doing this exactly from the link above worked for me.

Open PowerShell (as Administrator) and run this command (without the "")
"Get-AppxPackage Microsoft.SecHealthUI -AllUsers | Reset-AppxPackage"

After doing this, check your settings-> Privacy & Security-> Open Windows Security

Answer 2

Hello,

Same thing happening to me. It has been seen elsewhere On the Windows Insiders Page. Windows 11/Defender

Ok. Doing this exactly from the link above worked for me.

Open PowerShell (as Administrator) and run this command (without the "")
"Get-AppxPackage Microsoft.SecHealthUI -AllUsers | Reset-AppxPackage"

After doing this, check your settings-> Privacy & Security-> Open Windows Security

You're correct, that's the solution

https://answers.microsoft.com/en-us/insider/forum/all/unable-to-open-windows-defender/4348cb8f-c800-40d5-b3b3-791bf6723022

Answer 3

Before the jump to the Windows 11 preview, I did have a program called Advanced System Care installed as well as Avast Anti-Virus for a short period of time.

As lacrumb mentioned, these two programs could be the cause of your issue. Did you remove Avast with their uninstaller tool or did you just uninstall it. There is no removal tool for Advanced System Care that I am aware of.

It appears there may be remnants of Avast that was left behind, not enabling Windows Security to become active. Might be easier to get the removal tool, re-install Avast and then use the tool to uninstall.

You might also do a search through the registry for both of those programs and delete all related keys. Ensure you backup (export) your entire registry first prior to doing anything.

Regards,

Answer 4

Before the jump to the Windows 11 preview, I did have a program called Advanced System Care installed as well as Avast Anti-Virus for a short period of time.

Answer 5

Any 3rd party anti virus, security, cleanup programs EVER installed on the computer?