Hi @hubert.ropa
First things first. Could you please start with a clean Community EXE installation and have a look here:
You will see that the Studio Sign In will simply work for an attended scenario, no need to play around with the machine keys anymore.
The post I linked above also contains this link on how you could potentially setup your unattended license, although it’s a bit of a workaround at this point.
Anil_G
ashokkarale
Gautham_Pattabiraman
goprisko
rashmisingh2695
SorenB
Julian_Muhlbauer