Can not connect while running as service

We are having 2 locations to connect each other via Netcam…
When we run the Netcam as a service, the opposite side’s client can not connect to the site.
When we stop the service and start the server, clients can connect with no issue.
Do you have any insight into what might cause this issue?

Does it work with the web client?
First make sure all works on the server computer.
Sounds like a firewall problem. Turn off the firewall and check. If it works make sure that the NCS service can pass the firewall.

I had the exact same issue. Suddenly yesterday may cameras stopped working. In my case you were correct, it was the windows firewall.