I'm trying to set up a remote IP phone using an existing Linksys RV042 router. Some of the features of the phone work, but some do not. I have forwarded several ports to the phone system. But when I go to an online port scanner, it tells me that some of the ports I have forwarded are not open. I've used a few online port scanners and they all confirm the same thing. My RV042 is sitting behind a T1 modem/router. I'm wondering if the T1 modem has a firewall, too. Even if I turn the firewall on the RV042 completely off, the port scanners say all the ports are closed. The port scanners confirm that the ports I opened for the mail server and HTTPS are open, But the ports for the IP phone which are in the 4000 to 6000 range always appear closed. What gives?
I have this problem too.