I try to setup a VOIP trunk with 3CX to a Broadsoft platform. I got the following data from my VOIP provider: - Group Domain - User ID (Line ID) - Authentication ID - Authentication Password - Proxy server I.P. address. I use a general VOIP provider and enter the following Data: - SIP server hostname or I.P. = <Group Domain> - SIP server port 5060 - Outbound hostname or I.P. = <Proxy server I.P. address> - Outbound proxy port = 5060 - External number = <User ID (Line ID)> - Authentication ID= <Authentication ID> - Authentication Password = <Authentication Password> This does not work, I get a SIP 404 error (Not found) I tried to use the trunk with a X-Lite softphone and entered the following data: User Details: - User ID = <User ID (Line ID)> - Domain = <Group Domain> - Password = <Authentication Password> - Authorization name = <Authentication ID> Domain Proxy: - Register with domain an receive calls, enabled - Send outbound via Proxy, Address: <Proxy server I.P. address>. With this setup I get the VOIP account for the Trunk succesfully registred. Why is this not working with 3CX Generic VOIP Provider?