Outlook bounces....

Posted on 2011-02-15
Last Modified: 2012-05-11
we have an address that receives mail all the time but yesterday this bounced from someone:

From: Mail Delivery System <>
>Sent: Feb 14, 2011 2:40 PM
>Subject: Mail delivery failed: returning message to sender
>This message was created automatically by mail delivery software.
>A message that you sent could not be delivered to one or more of its
>recipients. This is a permanent error. The following address(es) failed:
>    SMTP error from remote mail server after RCPT TO:<>:
>    host []: 550 5.1.1 <>:
>    Recipient address rejected: User unknown in relay recipient table

Can anyone tell why this bounced?
Question by:lalexander53
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LVL 13

Expert Comment

ID: 34902566
Was it the only one to bounce? Did he try it again after that and get the same message?

Accepted Solution

OctInv earned 500 total points
ID: 34903100
It sounds like an anti-spam tactic. I am not sure what edge transport server / hosted solution you are using but many of them have a list of ligitimate recipients (some sync with AD, some are manual imports), and if an address is not on the list the system assumes it is spam and bouces it or drops it. Do you know if anything has been updated latley? You might want to check.

Expert Comment

ID: 34903273
>    SMTP error from remote mail server after RCPT TO:<>:
>    host []: 550 5.1.1 <>:
>    Recipient address rejected: User unknown in relay recipient table

This suggests to me that have dropped your address. try contacting them.

As I understand it, offer a forwarding service that appears to have (temporarily?) failed.

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