It worked with an original Win 8.1 Pro key, and after a very short automatic MS-update it was Win 10 Pro.. !!! Thanks.

William

It worked for one Laptop, with the generic key. On the other Laptop it did NOT. (error not a dig.keY bla bla..

To work with my own Original Key, where can I find the file containing the "PID" ...

I have an original CD with 64 bits Win 10 Pro for OEM, with a sticker with key.
I did a clean installation deleted the partitions in C:

I installed and see that it is the Win 10 OEM Home 1709 ...