Not working on Windows 2012R2

Hello. 

I am having big trouble accessing a Windows 2012 R2 system (with no display attached).

Everything works fine otherwise: on my old PC, new PC, old laptop and new laptop. But when I changed my server, I cannot access it.

I even tried setting up unattended access, it still does not work.

The errors vary, but there is no successful complete connection.

Erros:

- connection remains in 'connecting...' state

- screen cannot be captured 

- it connects but nothing else happens

Note that if I lock the station instead of disconnecting form within windows, I can get to the login screen but then I cannot continure from there. If I disconnect previously, then I cannot even get to the login screen.

Is there a special configuration needed so it can successfully work on W2012R2/no display ?