Hi,
The issue could be caused by third-party antivirus software blocking Windows Defender, a virus, or the fact that you have attached a work or school account.
- Please check if you have any third-party antivirus software installed on your computer, such as AdwCleaner, Avast, or similar applications. If you do, uninstall them completely, restart your computer, and then check if the issue is resolved.
- Go to Windows Settings > Accounts > Work or school account access and check if there is an organization attached. If there is, disconnect it and try again.
- Please download this file: https://catalog.s.download.windowsupdate.com/c/msdownload/update/software/defu/2024/02/securityhealthsetup_e16941e14861a6d24750ecdf05c548189b33182a.exe
Once downloaded, right-click and run as administrator.
Then check the Windows Security page to see if it works.
If not, restart your computer and check again.
- Please try scanning your computer using Microsoft Safety Scanner and check if you can open Windows Security afterward: https://learn.microsoft.com/defender-endpoint/safety-scanner-download?view=o365-worldwide
- Right-click your Start Menu and choose Windows PowerShell (Admin)
Copy and paste the command below and hit Enter:
Get-AppxPackage Microsoft.SecHealthUI -AllUsers | Reset-AppxPackage
Let the process finish, then restart your computer and check if the issue is resolved.