Package:X2Go Server
Version : 4.0.1.20
System : Ubuntu 17.04 Zesty Zapatus, Kernel 4.4.0-81-generic
Desktop: MATE 1.18.0

After Launching the Client, it shows a black Window, showing "Could not acquire name on session bus"

First I suggested to edit the file/etc/systemd/system/display-manager.service - but that is wrong, then 
the desktop on the machine will note come up : ***** WRONG : 
/etc/systemd/system/display-manager.service

[Service]
unset SESSION_MANAGER
unset DBUS_SESSION_BUS_ADDRESS
.....

***** /WRONG - Desktop Session will not boot this way (remote desktop is 
working) ***** /etc/x2go/Xsession.d/75dbus_dbus-launch # $Id:$ # In 
order to activate the session bus at X session launch # simply place 
use-session-dbus into your /etc/X11/Xsession.options file # STARTDBUS= 
DBUSLAUNCH=/usr/bin/dbus-launch if has_option use-session-dbus; then # 
changed rn am 26.06.2017 - $DBUS_SESSION_BUS_ADDRESS is not zero length, 
but : "unix:path=/run/user/1000/bus" # if [ -z 
"$DBUS_SESSION_BUS_ADDRESS" ] && [ -x "$DBUSLAUNCH" ]; then # old code - 
STARTDBUS will ne not set if [ -x "$DBUSLAUNCH" ]; then # new code - 
STARTDBUS will be set to yes STARTDBUS=yes fi fi if [ -n "$STARTDBUS" ]; 
then # Note that anything that is D-Bus-activated between here and # 
95dbus_update-activation-env will not have the complete environment # 
set up by Xsession.d, unless the Xsession.d snippet that sets the # 
environment variable also calls dbus-update-activation-environment. # 
See <https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=815503> eval 
$($DBUSLAUNCH --exit-with-session --sh-syntax) fi


***** /etc/x2go/Xsession.d/75dbus_dbus-launch - now its working as 
expected on my machine ... yours sincerely Ing. Robert Nowotny Rotek GmbH