Hi, I am replacing a MICS with a BCM400 3.7 Win NT system. I have installed several Norstar systems in the past. This will be my first BCM installation. This system is in use by a business with 4 CO lines and 25 Digital sets. The business will be requiring remote IP phones at a later time. I would appreciate any guidance you can provide on better understanding this system. I have the system, one combo 4X16 module, and a DSM16+ module that I am going to install next week. The system will have an analog module ATA8 installed, 10 Voice mail seats, and about 16 IP sets enabled at a later time. My questions are how do I go about updating the system, would there be any benefit in upgrading to 4.0, and in what order should the modules be installed? I noticed post about mismatching modules on different bus. I have already booted the system up and reconfigured the IP address and I am now somewhat familiar with accessing the system. I have not load any key codes at this time. I have had some trouble registering with Nortel to access the support pages. I will attempt to register again soon. Thanks for any help.