Hello, Spent a lot of time trying to get this to work. Ok here is what I have. I am running 3CX Phone System on a Windows 2003 server, all ports are open and working. I decided to go with Callcentric and have a Office unlimited account and paid for Calling time. I have 2 extensions set up right this second (100 & 101). I installed the 3CX VoIP Phone on one of my notebooks. When I dial my Callcentric number it recieves perfect, it is when I try to dial that I get several different types of errors. Does this look right? I have 2 extensions and none can dial out.