Windows 10: HELP! Need proof of purchase Product Key, Win10 Pro Upgrade

I lost my upgrade Product Key Home to Pro when system crashed and had to re-install the original OS from Dell. I do have the $100 receipt from MS Store for the upgrade last Sept but it doesn't provide the PK.

:)

 

Win10 Pro

Hi, I bought a Win10 upgrade license on my old laptop. At the time I had a lot of issues upgrading the OEM Win10 Home as the upgrade purchase didn;t come with a product key. After lots of phone calls with MS they eventually provided me with a product key
and the laptop was upgraded to Win10 Pro.

I now have a new laptop and still require the Pro functionality. Following the steps here (which also tells me my Win10 Pro upgrade license is transferrable):

How to Transfer your Windows 10 License to a New Computer

the OEMM Win10 Home didn't upgrade using the MediaCreationTool (it just offers to install Win10 Home), and the System > Upgrade and Settings > Activation upgrade function doesn't accept the product key I've purchased.

Any help would be appreciated - although useful Win10 is awful to upgrade and MS seem to have deprecatated a lot of their contact options.

 

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).

 

Upgrading Windows 10 Home to Pro with product key

I've used a Win7 Pro and Win8.x Pro Product Key [that had not been used previously] to Upgrade to Win10 Pro, only needed to do it in System,



It doesn't take long but an Internet connection at the time was helpful.