IntraWeb Archive

Notice to AOL, Comcast, and AT&T Users

Notice to AOL, Comcast, and AT&T Users

If you are using AOL, Comcast, or AT&T and are mad at us for not responding to your e-mail, please redirect your anger at the proper company. You should direct it at your ISP for running dubious and improper mass e-mail eating anti-spam procedures.

All three of these companies have been caught in shady activities involving interfering with users mail and traffic before.

Current Status

As these providers regularly change their methods and often do not care about their impacts, the status may change.

  • AOL: OK
  • Comcast: OK
  • AT&T: OK from Nov 15, 2008

AT&T (also includes SBCGlobal)

For about 2 years now AT&T has been sending fake failure replies back to many inbound senders to try to trick spambots into thinking the mail is dead. But to the rest of us it is just plain annoying to get a fake failure message each and every time we send a message to an AT&T user. Now it appears they eat the inbound e-mails as well, and have not notified their users about this switch.

AT&T this week put our mail server on a black list. However our server is not on any public blacklist, and our mail server is new from late September 2008, and our logs show no abuse or external usage.

Nov 13, 2008:  We finally received a reply from AT&T. They did not list any reason why they had our server black listed but have agreed to remove it with in 48 hours. We believe that a previous owner of our new IP Address may have allowed activities which caused AT&T to blacklist it.


Comcast most recently was caught intentionally inserting TCP reset packets to interfere with peer to peer, and even VOIP traffic. Now they are eating e-mails similar to AT&T, again without notice to their users.


AOL has a long history of not caring about how the Internet works or how badly they create problems. Now they are interfering with mail again. I have an AOL user who is complaining about our customers support for not replying. We have replied numerous times and even tried from external gmail and other accounts, yet none of our mail gets through. AOL returns to use a failure message like this:

Subject: Delayed Message: Original Subject

This is an informative message sent by
The server was not able to deliver your mail message to the following addresses:

  <> ( 421-:  (DNS:NR)

This is just a temporary error. The server will continue to attempt to deliver
the message. If the message cannot be delivered in the defined time limit you will
be informed again.

There are several problems with this. First they are responding with a temporary error, to something they are treating as permanent. So the sending SMTP servers will waste their time trying again, and most users will expect that it will eventually get through.

Second, lets try the link they suggest:

Now lets try their suggested reverse DNS search tool. If you ping which is the MX record for you will find that it is

So after we click proceed we get this:

So it says success, but evidently still hates the reverse entry somehow, but does not bother to say what. And a reverse DNS lookup confirms what AOL says.


We found what AOL hates. However their solutions generally do not effectively reduce spam, and only create problems. Furthermore it interferes with their users mail, and these users have no idea or notification of such behavior.