Originally Posted by A1BizCom
What was the issue/solution?

Turns out Nextiva doesn't use the default port of 5060. Once I set up the proper port(ask Nextiva) and forwarded it in the firewall it registered. Also, outbound CID couldn't be anything other than the username in sip carrier options until I turned P asserted ID to alternate. First time I've had to turn that on for any carrier.