How to get product key of old OS (Win 7) after upgrading to Win 10?

Kari said:

Already recorded two reinstalls on the same machin, one install on a new machine, all activated using the same retail key. At the moment recording the upgrade process to 10, then finally the new install of the original 8.1 which will no longer accept my product key.

Using one of my available 8.1 keys for this but what the hell, science is important

It might take all night before I have the video here. It's half past 8 PM here now but luckily I am an insomniac.

One must understand that individual failures do not constitute a company policy nor universal failure.

Many people have reported a successful upgrade to Windows 10, fully activated, then a failure of an activation on a subsequent clean install - only to go back and do an upgrade again and have everything succeed as it is supposed to.

NavyLCDR said:

Kari said:

The thing is, even if you could retrieve the product key of the underlying OS, it would be useless. If a valid 7 or 8.1 was upgraded to 10 and the 10 automatically activated, the underlying 7 or 8.1 key is flagged as used and can't be used to activate 7 or 8.1 on another machine.

The key of an underlying qualifying OS is gone and invalid as soon as the upgrade to 10 has been activated.

100% complete and utter nonsense.

NavyLCDR, I agree with you.

Quote from this post: Solved Windows 8 Pro license transfer a new Windows 8.1 computer?

The activation page shows the following message (see screenshot below):

This product key is being used on another PC. Please try a different key.

Note: Click on the Call support option (see screenshot below).

Note: The activation robot asks you how many PC's you have installed Windows on. The correct answer is number 1.

genet said:

NavyLCDR, I agree with you.

Quote from this post: Solved Windows 8 Pro license transfer a new Windows 8.1 computer?[/url]

I used to beta test Windows 7 and was always doing a clean install just about every month, and subsequently played around with Windows 8/8.1 and now Windows 10. I've got a couple of Windows 7 keys now in that "won't activate on the internet" window that I have to call Microsoft and tell the computer voice it's only installed on one computer in order to activate. And they are still good, after using them to upgrade to Windows 10 with.

Maybe Kari is in the same situation, I don't know. Each Product Key does have a limited number of times it will activate automatically over the internet within a certain amount of time but until Microsoft sees a heavy repetitive use of the same key, it can be activated by phone.

Now run slui 4 from a command prompt and attempt phone activation. You probably hit the online activation limit using the same key so many times in a short period of time.

Kari said:

[*]Reinstall 8.1 Pro on a new machine trying to use the same retail product key, resulting this:
<snip of pic - key didn't work>

Now that is interesting. The activation must use the original key then it seems.