He instalado un w10 pro y al inicio de la instalación en vez de dar la clave, pulsé que no tenia clave para activar despues de la instalacion.
Pues al intentar activar tras la instalación me dio error y me decia que no tenia una licencia digital valida.
Supongo que hay que meter la clave al inicio de la instalación que es cuando la pide. Lo intentaré mañana y a ver si funciona. Ya reportaré el resultado.

Just bought a license. Available right away, no problems with the activation. Thanks a lot, you are doing a great job! From a new loyal customer

Worked - One minor issue, but was my fault.
I had done a fresh install of 'Windows 10 Pro N'' and afterwards tried to use the key; this failed.
I re installed windows and provided the key during installation and it worked.

Fast payment processing and windows activation. The key works, thank you.

It simply works.
you grt the coad in the websight itself. no need to wait for the mail. but this means you can be confused as well