Interesting. I am a Comcast customer, and I get all my spam, I mean e-mail, without any problem. I have encountered issues sending e-mails to Comcast customers from my company (including to my own e-mail account as a test). As a network admin, I was able to read the reject messages that Comcast sent back, which even included the basic information to fix the problem, which took about ten minutes to fix in my case, and about four hours to take effect.

Do you have access to the bounce messages? Also would you be able to post the headers of a sample e-mail that is typical of the bounces? From reading your description of the problem, it seems that a majority of the e-mails are server or software generated, and that is where I ran into my problem. Is that the case?

__________________
The best way to learn anything, is to question everything.