Thanks for your reply.
I can see the https post leaving the application via the java console trace.
Tomcat also logs that the request has been received.
But a response is never sent to the application. Or, maybe it's sent and rejected.
Could you please post the error and tracing around it from the console?
This would help us understand and fix the issue that application was quietly exit without any user feedback.
Alternatively to this forum, you could file a bug against Java JNLP with the full trace log.