Cannot get a Teredo IP address

EDIT: When I now run the multiplayer connection tests it is saying 'Cannot get a Teredo IP address'.

Hey there, Soccer King6354! Factory resetting your console is an option that some users have found to resolve their Teredo IP error, however we encourage you to exhaust all troubleshooting with your network first. This thread is over a year old. Please post
up a new thread detailing what you're running into, your modem and router manufacturer and model, and troubleshooting you've completed. This way our community can get you the individual support that works best on the forums.

You, Sir, just solved this problem for me!

THANK YOU, THANK YOU, THANK YOU!

-Pete

Calm stated: "Consequently a time capsule on a different ISP with no additional setup works fine." The reference to "a" TC leads me to believe it was not necessarily the same TC he is now using with Comcast. If it is not, then it may be that the other TC
has a different firmware revision that plays better with Teredo and the one he is using now has the flawed version referenced in the links I posted and/or is configured differently. Regardless, due to the nature of the problem, it is most likely an issue
with Calm's router settings. At most Comcast may be able to help walk Calm through configuring it, but it may be that a firmware update/downgrade of the TC is required...

If it was a TC problem GZA, Calm, surely would've got the same error when he tried the connection with a different provider. That's my reason in thinking it's an ISP issue and not the hardware.