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Same here. Another option is to check if your Microsoft account is properly linked to your digital license in the activation settings.

This happened to me with an older Office version. Once support ended, I stopped getting security updates, which was a real concern.

Can confirm. Also, try clearing the TPM in your BIOS, as that can sometimes resolve Secure Boot detection issues.

You could also try booting from your Windows 10 install media and using the repair options to fix the startup. Another option is to check if a recent BIOS update is available from your PC manufacturer, as that can sometimes resolve compatibility hiccups.

+1 You could also try using the Media Creation Tool to do a clean install, but that will wipe your drive.

Yeah, that's usually the fix. Just be sure to save a backup before you toggle it on, as some systems act weird after enabling it.