I installed the production version and updated it to 5.0.43. I have narrowed the problem down to the following.
1) The system has Nvidia GPU. On a fresh install, Ubuntu 14.04 will load Nouveau driver. Everything works fine with this driver. I am able to create virtual desktops.
2) When I install the Nvidia Drivers the NoMachine Virtual Desktop creating stops. The connection is reset within a couple seconds without any error indication on the client side. It goes back to “Connect” screen on the client.
The behavior is repeatable by removing and installing nvidia driver.
Appreciate your help.