Windows 10: Win 10 Pro OEM Product Key will not upgrade from Home when reinstalled

I have a laptop with a win 10 Pro OEM.The laptop has been rebuilt several times to provide a fresh install of Windows 10 Pro without any issues.I am no longer to able to do this, i now have to install Win 10 Home and then upgrade to Pro but this fails as the product key is "Invalid" can anyone assist as the product key should be fine.

:)

 

Upgrade a Win 10 home OEM to Win 10 Pro OEM with Win 10 Pro OEM Key?

I recently purchased a laptop that has an OEM version of Win 10 Home on it.

I verified this by using : slmgr -dli.

Previously I had purchased an OEM Win 10 Pro Key.

Can I use this OEM Win 10 Pro Key to upgrade the OEM Win 10 Home to the OEM Win 10 Pro.

If so what are the steps to accomplish this?

In addition, I assume that is this is possible, that the current product key will be updated to the new product key?

The reason I am asking this is that it's my understanding that these product keys are tied to the bios on a name brand laptop.

TIA

 

Win 10 Pro upgrade using Win 8 Pro product key

I just bought a new computer running Win 10 Home. When I went to upgrade to Win 10 Pro using my Win 8 Pro product key from my old computer, the upgrade wouldn't activate.

Now I'm stuck with a bunch of error messages (mainly 0xC004C003) and am being told windows isn't activated. I can't seem to get my activated Win 10 Home back.

I don't have a product key for the Win 10 Home because it came pre-installed. There's no product code recorded on the packaging or labelling on the device.

So:

How do I either

• activate the Win Pro upgrade, or
• Get my activated Win 10 home back?

 

Upgrading to Win Pro

If you have a disc (DVD) version of Windows 10, it is likely OEM and an OEM Pro product key will usually not directly upgrade Home to Pro by simply changing the product key. If the product key is rejected by Windows 10 Home there is a workaround. Disconnect the computer from all sources of internet. Once the computer is disconnected from the internet, change the product key to VK7JG-NPHTM-C97JM-9MPGT-3V66T. Once the upgrade to Pro is finished, then you can activate it by changing the product key to your OEM product key for Pro.