Windows 10: Need to reinstall Windows 10 but cannot find Activation Key

I need to rebuild my computer but unfortunately, I cannot find the disk or activation keys for my Windows 10 computer. Is there a way I can retrieve it without buying another license?

:)

 

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.

 

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

Your ild keys should work but if you registered the key to your online ms persona (email address) it should be tied to your account , install without a key login with your credentials , then activate.

 

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.