Hello all, I am new to 3CX and just installed it - works great on my internal LAN however I am trying to set it up so that I can access it via external server. I have a Cisco 881w router as my main router and it was setup initially with port forwarding from 8000 to 80 since I also host a web server and my ISP blocks 80. Had to also configure the zone pairs to make this work. So so 3CX to work, what are the ports that need to be opened and does anyone have experience to configure this Cisco router to make it work? thanks for your help on this. Cheers!