Hello,
Here are some potential scenarios that might cause this behavior on Windows 11:
1.Corrupted Windows Store Certification: A corrupted Windows Store certification can prevent access to Windows Security. Reinstalling the Microsoft.SecHealthUI component can resolve this.
Open powershell window with admin access, paste the following command and press Enter to reset the Windows Store certification:
Get-AppxPackage Microsoft.SecHealthUI -AllUsers | Reset-AppxPackage
After the command is run successfully, reboot your PC and see if the problem is fixed once the next startup is complete.
2.Corrupted Windows Security Component: Upgrading to Windows 11 might leave some components partially corrupted, you may run the command suggested in
Windows Defender won't open? Here's how to fix it! (Windows 11) - Microsoft Community to fix it.
3.Interference from 3rd Party Antivirus Suites: Some third-party antivirus software can block access to Windows Security. Disabling or uninstalling the conflicting antivirus software can fix the issue.
4.System File Corruption: System file corruption affecting Windows Security or its dependencies can be an issue. Running an SFC and DISM scan can help.
Another user has reported that you can download the Windows Security App from the Microsoft website, then you will be able to launch the Windows Security app.
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