AOL rejecting mail from IP's w/o reverse DNS ?

Christopher X. Candreva chris at
Wed Dec 3 15:13:31 UTC 2003

Since I'm 99% sure the idea (or stupidity thereof :-) of blocking SMTP
servers without reverse DNS came up here in this discussion, I just ran a
manual queue run to clean out a queue, and saw this come up:

... Connecting to via
ESMTP mail_relay_in-xn5.9; Wed, 03 Dec 2003 09:59:55
220-America Online (AOL) and its affiliated companies do not
220-     authorize the use of its proprietary computers and computer
220-     networks to accept, transmit, or distribute unsolicited bulk
220-     e-mail sent from the internet.  Effective immediately:  AOL
220-     may no longer accept connections from IP addresses which
220      have no reverse-DNS (PTR record) assigned.
>>> EHLO

I don't know if this is new -- I don't recall seeing it before, but it
doesn't say they WILL refuse, just they may. If they do start blocking --
this WILL be an operational issue.

Chris Candreva  -- chris at -- (914) 967-7816
WestNet Internet Services of Westchester

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