Windows 10: Free upgrade from Windows 7 to 10 license key

I received a free upgrade from Win 7 to 10 several years ago during the free upgrade period. IA short time later I had to revert my PC to Win 7 because of a compatibility issue with software. I upgraded to Win 10 a few days ago because of another compatibility issue and Windows won't accept my license key. I get Error code: 0x803fa067. The only key I can find is the original Win 7. I can't find any record of MS ever giving me a new key with the free upgrade that was installed and then removed. I really don't know where to look besides email. The PC is listed in my MS account and shows it has W

:)

 

How to reinstall Windows 10 if my computers used the free upgrade from 7 and 8?

Will windows 10 still accept the license keys from 7 and 8 now if I reinstall my computer?

Does Microsoft keep a list of users who upgraded to Win 10 using their 7 and 8 keys so that when users need to reinstall windows 10 the old keys would work?

Do I need to call in Microsoft to ask them to activate my Windows 10 when I give them my win 7 keys?

Both computers are laptops. The windows 7 machine had the serial printed on the back, and I needed to enter that when I upgraded to 10. The windows 8 machine had the serial built in inside its boot system so I didn't need to enter the key when I upgraded to 10, but I did manage to write down the keys using a fetcher program.

 

Installing Windows 10 using Windows 7 key

Nope, you need to install Windows 10 first and make sure the Windows 7 key is transferred to your Windows account after you've installed Windows 10 (not quite sure how that works). I missed the last step and I could not activate Windows 10 after a re-install... Microsoft seem to have done everything they can to make it a PITA. Also, it's technically too late to do this now anyhow, as the upgrade offer has expired. But KMSPico works quite well...

As for getting rid of Windows, delete the Windows folder.

 

Windows 10 upgrade license

Ahem... lost my activation when upgrading from AMD Phenom II to my XEON...
Installed "legit" activated Windows 7 Ultimate x64, and yes i paid for the license originally, but that key no longer works.. i paid more than enough to MS *Shadedshun :shadedshu:
Anyway once 7 is installed.. go here... Download Windows 10
Click Upgrade Now, it will give you a download with an app that gives you legit activated Windows 10 based on your Win 7 activation.