Windows 10: Win 10 won't upgrade legal activated win 7 pro

Windows 10 Media-creation tool downloads and runs up until the point where it puts out a message that there is a problem with the Windows 7 product key. (sorry, I don't have the exact text at the moment)

This Windows 7 Pro 64 is an unquestionably legal oem installed OS and it was activated successfully.
The Windows 7 PC is joined to a domain whose PDC is Windows Server 2016 and it works in all respects -- so far!

I don't understand why Windows 10 would refuse to upgrade Windows 7.

I really need to upgrade this PC to Windows 10.

Ideas???

Thanks...

:)

 

win 10 activation

I have a legal Win 7 free upgraded to Win 10. In repair shop Win 10 Pro has been "installed" which I have noticed few weeks ago. I have tried to activate Windows with code on the bottom of my PC but I get message that this code is not valid for Win 10 Pro.

I don't really need Win 10 Pro but how to get back to my Win 10 and activate it?

Thanks in advance for helping me with this.

 

Win 10 activation

I did the upgrade to Win 10 from a legal win 7 and all went smoothly and activated. There was a driver issue with a serial port card which could not be fixed and was imperative to my work so I moved my hard drives to a different tower. Now win 10 is no
longer activated and gives me no alternative option than to purchase a license key. Any suggestions?