I am having a devil of a time troubleshooting my my ATT Microcell can no longer connect to ATT's servers.
After cutting all of the intermediate networking devices on my system out (firewall, switches, etc), I finally just hooked up a vanilla PC directly to my Motorola 6141 modem and used a port checking tool to check all the required (by the DPH 151 Microcell) ports for openness.
Sure enough, when connected directly to the modem, my PC cannot see and/or receive UDP 4500.
Obviously, this is not listed on Comcast's published list of blocked ports.
And yes, all software firewalls were disabled on the PC at the time of testing the ports for openness.
If I talk to Tier 1 tech support at comcast, they tell me that either 1) That port is not blocked or 2) that port is not on Comcast's list of blocked ports.
But my results contradict that statement.
Desperate for any thoughts or avenues of approach to Comcast to determine whether
1) The port being closed to a Northern NJ residential customer is inadvertent or temporary
2) There is a more definitive way to test, from my end, whether the port blocking is occuring due to Comcast.
Help please!
