AT&T Postmaster Website
E-mail Error List
This page contains a list of possible solutions to the more frequent e-mail related errors experienced by non-AT&T customers attempting to send e-mail to AT&T Internet customers. Click on the error message for additional information.
There seems to be a failure in your IP reverse DNS lookup. Your IP address must have a valid reverse DNS entry to send mail to the AT&T domain. Please correct the error or contact your service provider for assistance before trying again.
The system administrator should consult http://www.faqs.org/rfcs/rfc1035.html.
The sending system has requested more resources than are available at the moment.
The sending system should re-try.
The sending system has been identified as a source of spam.
Please see http://www.att.net/general-info/521.html for more infomation.
The account of the BellSouth customer is suspended.
This error message indicates that the recipient of the e-mail has incorrectly set up a forwarding address. To resolve this issue do the following:
Contact the customer directly.
We were unable to verify the identity of the sending system.
This error message indicates the recipient mailbox is full.
Administrator of sending system should enter correct information in DNS (domain name system)
The sending system is not recognized as a valid source of e-mail.
Correspondents should use registered mail systems provided by a major ISP or hosting service.
The sending system exhibited behavior associated with spammers and was blocked.
After taking steps to mitigate their spam or virus problems, the adminstrators of affected systems can send unblock requests from http://www.att.net/general-info/block_admin.html