Hub 3 port forwarding does not work for a specific port
Hello there. Just switched to Virgin Media so I have a freshly installed Hub 3 on my home network. I have been able to open a few ports for forwarding, but there is an essential - port 5000 - that does not work. After I do the settings, the hub reports that the port is open, but in fact when I test it with the "yougetsignal.com" port tester, then it turns out the port is actually closed. I have opened a number of random ports and they open just fine, immediately. But port 5000 will not budge (also not after rebooting router etc).
I tried to call Virgin Tech support, but could not connect and then Virgin sent an email to say I better ask the community about port settings... Interesting, that.
Anyway, most grateful if someone has an idea of what might be the matter here. M