Windows Upgrade Help and more

I had the same problem. A clean install of Windows 11, instead of the upgrade, finally fixed it for me. Let me know if that works.

You could also try using the Activation Troubleshooter again, but this time choose the "I changed hardware on this device recently" option. Another option is to contact Microsoft support directly—they can often push a reactivation through on their end.

Agreed. The Rufus trick is solid, but with that CPU, you might be looking at a clean install bypassing the checks entirely.

You could also try restarting Windows Explorer. Open Task Manager, find it under Processes, right-click and select Restart.