Hi,
the display service on the server can’t start up because it cannot find any free TCP port in the given range. This range can be modified to avoid conflicts with other applications as explained at point 6 of the following article:
https://www.nomachine.com/AR11L00823
However the fact that all those ports are unavailable is abnormal and it should be checked if there is an application that is misbehaving. You can see yourself what are the busy ports in the nxserver.log file:
2020-09-28 11:40:57 903.811 29296 NXNODE TCP port '7002' is used by another application.
2020-09-28 11:40:57 905.853 29296 NXNODE TCP port '7003' is used by another application.
[...]
2020-09-28 11:40:58 376.810 29296 NXNODE TCP port '12200' is used by another application.To check what application is keeping those ports busy you may try one of these methods: