Hi, This is all new to me and I need a bit of help please with setting up my system to register an external extention. I am running version 3.1.2434 of 3cx on SBS 2003 and have managed to get up and running with X-lite softphones on my internal network but I want to give an extention to a party out side of my network. I also have a dynamic dyndns account that I use to map my dynamic external IP do a domain name. This is working well at the moment for small website I host. I would like to know how I can set my domain name in 3cx software so that I can have users connect using names like sip1@fqdn? I have port forwarding set up on my dlink DSL-504T router which is the gateway to my network, for all the necessary ports specified in the 3cx documentation. I have also got stun.3cx.com set as my stun server but when I try and register my external extention, X-lite throws back a timed out message. Could some one please point me in the right direction? I should also mention that my sbs has 2 nic's. Dont know if this makes any difference??? I was kind of curious if this was the issue? How does the 3cx software know which nic to listen on? Seems like it is only listning for registration requests on port 5060 of the internal nic... Thanks in advance.