Fedora Client/Server Remote RDP Problem

Hi, I have two new Fedora installations. One (Server) on a HP ProDesk Mini and one on my laptop.

I activated the RDP Server (3389) and added two users on the server. Tiger VNC (closed connection) and Remmina show my the Login screen but close the window after pressing Enter (with User/Passwort).

KRDV gives me this information:

connecting to sesman on sesman.socket
sesman connect ok
Performing login for x
sending login info to session manager. please wait…
User does not exist, or could not be authenticated

Somebody knows why?

Do you have KDE installed at both ends?

Yes I have. I can also run Cockpit for the HP from the Laptop.