Windows 10: Trying to upgrade my sister's computer. (With a bugged product key)

So I found the weird "UpgradeWindowsApp" and I copied it on my USB flash drive and I will put to my sister's somehow unupgradable computer. I think it won't work because of the product key...

:)

 

Cannot upgrade to Windows 10 - Unique Product Key situation

No... let me try again.

• Old computer is running Win7 Pro (SP1) with a Product key I have from a few years ago. The Product is activated already, but I do NOT use this computer at this point, so I didn't worry about using the Product key when moving to the new computer (see below).
  
• New computer is running Win10 Pro, with data and OS migrated from the Old computer, (same Product key as above), then Upgraded to Win10 (without getting a new Product Key).

What I am trying to do now...

• I want to upgrade the OLD computer (Win7 Pro) to Windows 10... using a new Product Key I just purchased.
• I have tried to do this internally, and also using the ISO burned to a thumb drive. But it does not want to work.
• Steps:
  • Start from USB drive.
  • Enter New Product Key (or click "I don't have one").
  • Install initiates and then tells me to restart from Windows and then open the installer again to continue.
    • At this point, I actually need to Quit the installation to restart the machine.
  • When restarted, I go to the USB drive and restart/resume the installation process.
  • I have tried to download and not to download updates, but when the installation fails, I see the message, "Something happened" and "Setup has failed to validate the product key".
  • NOTE This happens if I enter the NEW Windows 10 Product Key, or if I skip that step (which I assume means that it will use the old Windows 7 Key for the upgrade).

 

Two Computers Activated With The Same Product Key

I upgraded mine from Windows 10 Home, to Windows 10 Pro. Windows was oringally installed as fresh on both computers.

Bother computers had their own product key.
I have two Windows 7 Ultimate key, which I used to upgrade my Windows 10.

Yesterday, while working on my Sister's and her husband's computer, I decided to give them an upgrade, and chose the Windows 7 Ultimate one, to see what'll happen. It worked.

Weird thing is, the product key I used, is changed (not the same as the one I entered), probably becuase there is no Ultimate version of Windows 10.
A even weirder thing is, both computers have the same product key. My computer was off when the other computer was being activated. When I get home, I expected and activation issue on my computer, but so far none.

I tried to change the Windows 10 product key to another Win10 Pro, but when I use ProduKey, it still shows the same key.

 

Convert a Windows 8pro product key to a Windows 10pro produkt key

Hi Andre,

Thank you for contacting Microsoft community.

I suggest you to Uninstall the license using the following steps.

• Press Windows key + X
• Click Command Prompt (Admin)
• At the command prompt, type: slmgr.vbs -upk
• Press Enter, this will uninstall the product key from the computer.

Further on, install Windows 8.1 activate the copy with the product key on the new machine. Then again upgrade the same to Windows 10 using Window Update or Media Creation Tool.

Hope this information was helpful and do let us know if you need further assistance. We will be glad to assist.