I have setup the 3cx windows phone app for work on my Lumia 950 running windows 10 and have opened the config file for settings etc. Noticed a strange problem, the app registers fine via mobile data and my work WiFi connection. However on my home WiFi network it fails to register. Strangely on the home network connected a PC connected to the same router (Virgin Superhub 3) can connect fine using the 3cx windows desktop client. I also tested the mobile app at a friends house, again with the same ISP but running the older Virgin Superhub 2 and the problem is present there as well. In trying to troubleshoot last night I tested accessing my company's out of office tunnel URL from web browser on the working PC and this resolves, however on my windows phone it fails when connected to the WiFi. So the issue is obviously relating to the Virgin superhubs blocking the traffic on WiFi for some reason. I tried disabling the firewall on the superhub but alas made no difference. I want to setup firewall rules just in case this may help, what are the full list of ports required for the windows phone app? Failing that I will try setting the superhub to DMZ to my mobile to see if that allows the app to register. Failing that then looks like I'll have to set the superhub to modem only mode and use a separate router for providing connection to my LAN/WLAN. Thanks in advance!