Netmeeting not connecting

I have been able to connect to two other different computers in different towns with netmeeting before but when i try to connect to my two computers at home with netmeeting i can’t do it.
The way that my two computers connect to the internet is a line goes from my high speed modem to a switch where i have my two computers connected to. I checked the drivers on the windows 98 computer (one windows 2000)for the nic card and all is fine and it is able to connect to the internet.
But i can’t connect through netmeeting.

Any thoughts?