Our university just received notice from AT&T that our e-mail is being blocked without much explanation. As all universities send e-mail to the students and employees, it is impossible to tell what triggered AT&T's actions. Does anyone have an AT&T contact? If you are from AT&T, please contact me off-line. Thanks. matthew black e-mail postmaster california state university, long beach -----Original Message----- From: test_reply@att.net [mailto:test_reply@att.net] Sent: Wednesday, January 28, 2015 4:58 PM Subject: Blocked Email Notification Dear Postmaster: We are writing to let you know that we are blocking messages addressed to one of our customers at the domain att.net by one of your customers at domain csulb.edu. The stream of messages coming from your system appears to consist mostly of unwanted commercial e-mail (UCE, or "spam"). To protect our system and to ensure that it operates well for all of our customers, we have decided to block all messages originating from your system. Please consult your logs to see what might be causing this situation and how it can be fixed. Then visit http://rbl.att.net/block_inquiry.html to request a removal of the block. Most requests for removal are honored within two days. The specific error message received by your customer was: 550 Error - Blocked for abuse. See http://att.net/blocks Thank you for your assistance in helping our respective customers communicate. Best regards, The AT&T Mail Team.