Hi Tinywolf,
I think you’re talking about Windows, but I’ll also give the commands for Linux, just in case
Windows
Open the CMD console as administrator and move to the bin folder under the NoMachine installation directory and run:
e.g.
C:\Program Files\Nomachine\bin\nxserver --start
C:\Program Files\Nomachine\bin\nxserver --stop
C:\Program Files\Nomachine\bin\nxserver --restart
Linux
/usr/NX/bin/nxserver --start
/usr/NX/bin/nxserver --stop
/usr/NX/bin/nxserver —restart
The port can be changed by editing the server.cfg file
Windows
It is located in the etc directory in the folder where Nomachine was installed
 e.g.
C:\Program Files\Nomachine\etc\server.cfg
Key – Port 4000
Linux
/usr/NX/etc/server.cfg
Key – Port 4000
After changing the port it is necessary to restart NoMachine, use the restart command, examples of which I have given above.
Ragards,
Tom