where is the windows product key?

Hi all

I bought a brand new xps13 with windows 8.1 preinstalled. I upgraded to Win10 successfully. Furthermore I created a Windows 10 install image using the Microsoft tools.

Afterwards I formatted the disc and re-partitioned it to install windows and Linux next to each other. When I installed Win10 from that image, everything worked fine except for the fact that I don't find the product key. There is no sticker anywhere and it does not read it out automatically.

Secure Boot is off, Firmware TPM 2.0 is switched on.

Any ideas? If I buy a notebook with Windows pre-installed I somehow assumed, I will get a valid key as well :-)

best regards

Carolin