I can confirm that with this command the server starts without problem and the license warning disappears. So it seems that this problem occurs only when you start/stop the server from the GUI
Hi graphixillusion, we released an update, 9.2, which fixes some issues related to the nxservice. Can you update your installations and confirm that you are no longer encountering the expired message?
Sadly i still have it, even with the 9.3.7 version. The message appears if you stop the server from the UI, and it will never starts back (always from the UI). If you want to make it works again you need to manually start the nxservice as Guro said in his post above…