Windows 10: Key from previous upgrade 7 to 10, newly reset to Win7, would like to upgrade to Win 10

I recently today had to reset my desktop computer, which was initially set up using a genuinely acquired Windows 7 key of which I have the CD key for. After reformatting the drives of the computer and booting into Windows 7, I am no longer given access to upgrading to the free previously offered Windows 10, of which I had prior. It shows up on my Microsoft account that Windows 10 Home was in fact installed on this machine prior to me reformatting it, but I am unable to get a usable CD key for it. I have downloaded the Windows 10 ISO through the upgrade to windows 10 app, but do not have a key that works for it since it asks for a windows 10 key.

From my previous upgrade to windows 10 at least 4 years ago I was never given a key, but do still have my windows 7 product key that I had to use once again to boot into windows 7. The microsoft website still lists this account as having my desktop as a windows 10 device with home.

:)

 

dual boot win7 + win 10 "upgrade"

I think so. You'll have to download the install media for Windows 10 via the Media Creation Tool. When it asks for a key, type in your Windows 7 key. It should activate...both Windows 7 and Windows 10 will be locked to your hardware profile.

The activation servers do not forget your Windows 7 license upon upgrading to Windows 10. You should be able to run both on the same hardware because, technically, they're both still licensed.

It used to be the former (had to do an in-place upgrade) but now you can also do the latter. The Windows 10 setup will accept Windows 10, Windows 7, and Windows 8.1 keys.

 

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.

 

dual boot win7 + win 10 "upgrade"

alright idiot question time, as my search foo must suck and gets possibly out of date info

currently have win7 pro x64 and want to run win10 ONLY for games to take advantage of dx12. I know I can get the "upgrade" to 10 and then revert back to 7 BUT can I dual boot both? does the win7 key get blown away once 10 is installed?

basically does microsoft allow both to run? not at the same time of course but dual boot with only one or the other active at one time.

as for installing, do you still have to upgrade to lock in the key to the current hardware, then do a clean install and use that win10 key? or can I just install win10 clean with the win7 key to begin with? there were a few
variants on how that worked..

sorry for noobish question but most stuff I found searching was for preview builds of 10 that were not tied to the existing OS key,