New mobo - Win 10 won't install due Cannot read product key warning

New mobo (old one died) and most everything else incl 500 gb NVMe S.2 SSD

I want to put a fresh install of Win 10 Pro on that SSD. Microsoft account knows my product key.

The USB install media I used to rebuild the old computer as it was dying reports "Windows cannot read <product key> from the unattended answer file." Never saw that before - ever! Even when installing Win 10 on a friend's machine from same USB chip.

New machine boots from standard SSD scavenged from old machine but i want OS on the s.2 drive.

I would create a fresh, new Windows 10 installation USB flash drive using the tool from Microsoft:
Download Windows 10

This product key thing seems to be a killer. NAVY Lcdr (been there, done that in a P2V) suggested downloading a new Windows USB flash drive, which I did. Plugged it into the new box and ... "Cannot read product key ..." I now have 3 USB chips doing that with this new build.

I made one of those USB install chips a year ago, took it to a friend's house, and upgraded his Win 7 to Win 10 WITHOUT A HITCH! "Cannot read ..." is new for me! Having had difficulties with my old install of Win 10, I used one of those original chips last month to install a new version of Win 10 pro onto an SSD attached to the failing Asus mobo and it WORKED just fine! New box, it doesn't work - none of the install chips work.

I'm a geologist, what do I know?

Does the computer have a DVD drive? If there is a DVD in the drive, eject it

Are you saying that you selected "activate later" and it still wants a key? Now that's really strange, I did that for all three of my installs and it never once failed to proceed to at least install the system???

Soapm said:

Are you saying that you selected "activate later" and it still wants a key? Now that's really strange, I did that for all three of my installs and it never once failed to proceed to at least install the system???

It appears to be an error message that comes up first thing after booting from the USB drive. It doesn't even get to the first screen to enter language and keyboard. The user never has a chance to do anything to get past it.

You can google it. Ejecting DVDs and unplugging anything not need for the install such as extra drives seems to be a common solution.