Hello. Are you signed in with an Administrator account?
- Check Settings > Accounts > Your info to see if your account is Administrator.
- If not, change it to Administrator.
- If your account is already admin, some settings may block Windows Security. You can check protection status by running PowerShell as admin and entering Get-MpComputerStatus.
- Windows Security still updates automatically through Windows Update even if the app won’t open. Check updates in Settings > Windows Update.
- You do not need an IT helpdesk for a personal device; the message is normal if policies are blocking access.
Best regards,
Arlene D.