I have inherited a Genesys Cloud organization and I am currently troubleshooting a SIP 403 Forbidden error on our primary BYOC Cloud trunk. This error occurs specifically when attempting to place outbound calls to international destinations. I have verified that the international dialing permissions are enabled for the site and the individual users. The trunk status is shown as ‘In Service’ in the Telephony settings. What are the common configuration oversights that result in a 403 Forbidden response from the carrier despite a valid trunk registration?
I deal with these SIP errors all the time and it is incredibly frustrating when the UI tells you everything is fine. A 403 usually means the carrier is rejecting your specific outbound identity. Even if the trunk is ‘In Service’, your carrier might be blocking the calls because the CLI you are sending is not in a format they recognize.
I suggest you check your E.164 formatting in the trunk settings. I have a custom dashboard that monitors these signaling errors in real time via WebSockets because the standard logs are useless.
Hey. Welcome to the world of inheritance! I had to fix this exact issue after our SSO migration. Check your ‘Outbound Calling’ settings on the trunk.
There is a specific checkbox for ‘Prioritize SIP Trunk Caller ID’ that can cause major issues if your carrier is picky about the from-header. Also, make sure you are not trying to send a P-Asserted-Identity that the carrier has not whitelisted.
It is usually just a simple mapping error that takes forever to find.
My agents are complaining about this constantly! They try to call a customer back in Europe and the call just drops immediately. It makes my supervisor dashboard look like we are having a massive outage. If this is just a ‘simple mapping error’, why is it so hard for the platform to give us a clear error message? I have thirty agents sitting idle because I cannot trust the outbound dialing to work correctly today.