Try reading this link
http://www.comcast.com/Support/Corp1/FAQ/FaqDetail_2577.html
Hope this helps.
Have Windows XP and Comcast broadband and NORTON...I just updated Norton last night..and now my email will NOT go thru...everytime I update this happens and I end up going back to before update...but I think I NEED the updates..so how do I get my outbound mails to go now?

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