The Windows key that I had been using for years stopped working. It was an old Win 8 key that I had updated to 10 then 11. Had to refresh the OS due to a random corruption and my Windows key wouldn’t verify. When I contacted Microsoft support they told me that since I don’t use a Microsoft account my registration wasn’t backed up. They don’t accept upgrades from Windows 8 anymore, so I would have to buy a new key. Instead I found a new OS.