Wrong cd key

You can use only one computer with a Product Key. OEM versions are tied to the computer they came installed on. Retail versions can be installed on a Replacement computer as long as the original installation does not exist. Win7 had a COA/Certificate of Authenticity sticker with the Product Key on it. Win8/8.1 obtained pre-installed did not, had it encoded in the BIOS [at least on the ones I bought and have worked on]. Your mention of the retail box begs the question, was it a Custom computer with Windows purchased separately and installed by the builder or an OEM/Brand name computer?

As long as your Windows 10 Pro is activated with a digital license and the Windows 10 Pro product key ends in -3V66T, you are fine.

swarfega said:

ah it is the -3v66T. I do have an activated Windows 10 in vmware. But I wonder why its not using my retail key.

Because the first Windows 10 originally on that computer came from an upgrade from Windows 7/8?

swarfega said:

Yes I did the free upgrade before getting a retail box.

Now you have the retail product that you can save and use for a new installation! I would look at it as a good thing. As long as you have a legit license for every Windows 10 installation that you have, that's all that matters.

swarfega said:

Yes I did the free upgrade before getting a retail box.

Are we talking about different computers where the free upgrade is still on the computer first installed on? The Digital Entitlement is associated with your Microsoft Account. I just set up a new computer that came with Win10 Version 10240 [the original RTM], logged into my MS Account and got it Activated. It did take several hours to get it Upgraded and updated to the latest version last week, 1607 Build 14393.351, and now on Build 14393.447.