Hi, take a look at point 4 in the following article:
https://kb.nomachine.com/AR04K00667#4
If there are multiple desktop environments, you can configure NoMachine to provide users the list of all the available desktop types installed and configured on the system (i.e. available in /usr/share/xsessions).
Set ‘xsessions=1’ in the ConnectPolicy key in /usr/NX/etc/server.cfg:
ConnectPolicy autocreate=1,autoconnect=1,automigrate=1,desktop=0,dialog=0,xsessions=1,udp=1
Removing the # from the key. Then when connecting, NoMachine will show all the DE options available.
Or to show XFCE, you can set the DefaultDesktopCommand key in node.cfg:
DefaultDesktopCommand “/usr/bin/startxfce4” (see point 2.1 of the same article).