Exchange is blocking incoming AOL Messages (421 4.3.2 System not accepting network messages)
Posted on 2013-10-17
We're having trouble receiving a client's email messages that are being sent from AOL Mail to our Exchange server. AOL Postmaster replies with a rejection email listing our mail server and the following error: "421 4.3.2 System not accepting network messages (in reply to end of DATA command)" We've white-listed our address through our firewall but the message still can't come through. We're able to send outbound messages to the AOL account but not inbound. Error message below:
From: Mail Delivery System <MAILER-DAEMON@AOL.com>
To: XXXXXXX <XXXXXXX@aol.com>
Sent: Wed, Oct 16, 2013 2:40 pm
Subject: Undelivered Mail Returned to Sender
*** ATTENTION ***
Your e-mail is being returned to you because there was a problem with its
delivery. The reason your mail is being returned to you is listed in the
section labeled: "----- The delivery status notification errors -----".
The line beginning with "Diagnostic-Code:" describes the specific reason
your e-mail could not be delivered. The following lines contains the
RFC822 header of the original email message.
Please direct further questions regarding this message to your e-mail
----- The delivery status notification errors -----
<XXXXXXX@aatel.com>: host mail.XXXX.com[XXX.XXX.XXX.XXX] said: 421 4.3.2
System not accepting network messages (in reply to end of DATA command)
Anyone run into this or know the problem?