It has been quite a while since we have worked on our client's SL1100. We got the third-party sip license and it is installed, I think. We already had a sip device installed back when we first put this system in. I cannot get this thing to register to the system. I am using the PCpro and I am looking under the 15-01, 15-05, and the 15-16 programming. the other sip extension shows up as SIP in terminal Type with no MAC all under the 15-05 IP phone Basic setup. I am at a loss.