Any mail admins here?

Ken Chase math at
Tue Apr 12 15:31:59 UTC 2016

Got this a few months ago, posting publically so it makes it into the archives
for the next guy.

  > Thank you for contacting the AT&T Postmaster.                                             
  > We need the IP address of the server sending mail from you to our customer/s.             
  > This information is provided in the non-delivery report that would be returned            
  > to you in the event that there was a problem with mail delivery.  If your mail            
  > server truncates that part of the error message, it may be necessary for you              
  > to conduct a manual session with our mail server to capture the blocked IP                
  > address.  If you do not receive a rejection message then your messages are                
  > potentially being filtered as bulk.  If you believe that to be the case, email            
  > mail-abuse-bulk at and request the Bulk Mail form to be                     
  > whitelisted.                                                                              
  > The more information you can provide about what you are trying to accomplish              
  > and the specifics involved the easier it is for us to help you.  Please reply             
  > to this message with as much detail about your problem as possible, but                   
  > specifically the points touched on above.                                                 
  > Regards,                                                                                  
  > Postmaster                                                                                
  > AT&T Client Security Management                                                           
  > abuse_rbl at                                                                   

On Tue, Apr 12, 2016 at 09:31:51AM -0400, Jeremy Parr said:
  >I have two spam filters that relay outbound mail for a few dozen companies,
  >and as such generate a fair amount of traffic. We are fairly strict with
  >the spam filtering on outbound mail, but somehow end up blacklisted by
  >ATT/Prodigy/Bellsouth a few times a year.

Ken Chase - math at

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