If you see a response code 403 on the events list in the [Start/Shutdown] page, followigng case may be the case of the issue.
The registering destination server (ITSP, SIP trunk) returned an error code 403.
– Check your user/password or the other registration settings.
– Contact your ITSP/SIP trunk and ask why the response code 403 is returned.
The SIP server does not have a global IP address interface while the registering destination is a global IP address.
– Set a global IP address as an interface address at [SIP SERVER] > [Configuration] > [System] page. You may need port fowarding settings at your router. Please refer to How to set port forwarding? and Using Brekeke PBX with a firewall.
– Remove the following line (or change the right side to false) from the rule “Thru Register” in the Dial Plan.
&net.registrar.onlyglobal = true