Windows 10: upgrade from 8.1 to 10 home, prod key not recognized

I purchased the product key from Microsoft but when I enter the last digit it won't accept the key as valid.

:)

 

Windows 10 Prod key shows different

I have installed windows 10 pro on newly installed pc, I purchased a key while back i used an app called prodkey to find what the prod key is so i could use the same key for new pc. however when i activate with key that i bought Prod key reports it as a different key all together *Confused I guess im little confused on this as well with how it handles License keys like it is activated but not - lot different than Win7. Does windows 10 actually require a key after a fresh install, the step where it asks to put in product key I skipped that step as i would do it later but when i go to System in control panel it says Windows is activated huh? so i selected change product key and put in the key i purchased not sure why the app prod key shows a totally different prod key from C:\windows.

 

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.

 

windows 10 key

Now that I have finally upgraded from Windows 8 to Windows 10 will my Windows 8 key work with a fresh install of Windows 10?