I just installed a 60 day trial of SLES 15. I choosed SLES for SAP install option and left packages at the default values.
Now if I connect from Windows 10 via RDP, the connections almost all fail. Maybe 1 of 10 work, mostly after reboot. mstsc is setup to use only 24 Bit color depth.
xrdp and sesman log level is set to info. Firewalld is shutdown (machine is already in DMZ).

[20190605-13:14:15] [INFO ] xrdp_wm_log_msg: Please wait, we now perform access control...
[20190605-13:14:15] [WARN ] getsockname() failed on socket 15: Bad file descriptor
[20190605-13:14:15] [INFO ] xrdp_wm_log_msg: Reply from access control: Success
[20190605-13:14:15] [INFO ] xrdp_wm_log_msg: sesman connect ok
[20190605-13:14:15] [INFO ] xrdp_wm_log_msg: login successful for display 201
[20190605-13:14:15] [INFO ] A connection received from ::1 port 33238
[20190605-13:14:15] [INFO ] Access permitted for user: admin
[20190605-13:14:15] [INFO ] A connection received from ::1 port 33240
[20190605-13:14:15] [INFO ] ++ created session (access granted): username admin, ip ::ffff: - socket: 11
[20190605-13:14:15] [INFO ] starting Xvnc session...
[20190605-13:14:15] [INFO ] calling auth_start_session from pid 18972
[20190605-13:14:15] [INFO ] Xvnc :201 -auth .Xauthority -geometry 1920x1080 -depth 24 -rfbauth /home/admin/.vnc/sesman_passwd-admin@localhost:201 -bs -nolisten tcp -localhost -dpi 96
[20190605-13:14:16] [CORE ] waiting for window manager (pid 18973) to exit
[20190605-13:14:16] [CORE ] window manager (pid 18973) did exit, cleaning up session
[20190605-13:14:16] [INFO ] calling auth_stop_session and auth_end from pid 18972
[20190605-13:14:16] [INFO ] ++ terminated session:  username admin, display :201.0, session_pid 18972, ip ::ffff: - socket: 11
2019-06-05T13:14:15.928142+02:00 localhost systemd-logind[2507]: New session c12 of user admin.
2019-06-05T13:14:15.928974+02:00 localhost systemd[1]: Started Session c12 of user admin.
2019-06-05T13:14:15.932982+02:00 localhost xrdp-sesman: pam_unix(xrdp-sesman:session): session opened for user admin by (uid=0)
2019-06-05T13:14:16.461481+02:00 localhost xrdp-sesman: pam_unix(xrdp-sesman:session): session closed for user admin
2019-06-05T13:14:16.463864+02:00 localhost systemd-logind[2507]: Session c12 logged out. Waiting for processes to exit.
2019-06-05T13:14:16.468284+02:00 localhost systemd-logind[2507]: Removed session c12.
Xvnc popup shows:

Any idea what's going wrong?