#5.7.1 smtp;550 5.7.1  Relaying denied

Posted on 2006-07-19
Last Modified: 2012-05-05
Why would I receive this realy denied, when I am the one sending the message, I do have relay permissions
because I am an authenticated user in the domain. There seems to be just two people I really need to email
that cannot receive my mail sporadically....Any help would greatly be appreciated...

Your message did not reach some or all of the intended recipients.

      Subject:      Lowes attachment number 2
      Sent:      7/19/2006 3:31 PM

The following recipient(s) could not be reached: on 7/19/2006 3:32 PM
            You do not have permission to send to this recipient.  For assistance, contact your system administrator.
            <MYSERVERNAME.COM #5.7.1 smtp;550 5.7.1 <>... Relaying denied>
Question by:ittechie100
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Author Comment

ID: 17141424
I got the above error when trying to send an attachment. Plain text goes right through ???
LVL 104

Expert Comment

ID: 17141707
Are you sending from Outlook or an SMTP client?
What does message tracking say?


Author Comment

ID: 17141711
Can send to any other domain fine it seems... ???
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Author Comment

ID: 17141870
Sending through Outlook client.
LVL 104

Accepted Solution

Sembee earned 250 total points
ID: 17150416
If you are sending through the Outlook client, but this is the only domain that you have problems with, then it has to be an issue with the remote domain. They are blocking your emails in such a way that triggers the cannot relay message.

Single domain issues I don't find worth the hassle, as they will usually say that there is nothing wrong.
Instead, simply configure an SMTP Connector to route email for that domain through your ISP.


Author Comment

ID: 17155212
         <MyExchangeserver.COM #5.5.0 smtp;550-MYIP  blocked by ldap:ou=rblmx,dc=comcast,dc=net>

What would cause this error ? I haven't seen it before.
LVL 104

Expert Comment

ID: 17157314
That is comcast's own blacklist. You can speak to them about getting off their list.


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