On Sun, 22 Jul 2007, William Allen Simpson wrote:
Comcast still blocks port 25. And last week, a locally well-known person was blocked from sending outgoing port 25 email to their servers from her home Comcast service.
MSA port 587 is only 9 years old. I guess it takes some people longer than others to update their practices. Based on what I know how comcast's abuse systems implement their port 25 restrictions, I think it is extremely unlikely it was based on other people having her e-mail address in their Outlook programs. Some people complain ISPs refuse to take action about abuse and compromised computers on their networks. On the other hand, people complain when ISPs take action about abuse and compromised computers on their networks. ISPs are pretty much damned if they do, and damned if they don't. Several ISPs have been redirecting malware using IRC to "cleaning" servers for a couple of years trying to respond to the massive number of bots. On occasion they pick up C&C server which also contains some "legitimate" uses. Trying to come up with a good cleaning message for each protocol can be a challenge. Yes, false positives and false negatives are always an issue. People running sevaral famous block lists for spam and other abuse also made mistakes on occasion.