SBS 2011 and Mx Logic Setup send connector error 451 4.2.1

Posted on 2011-04-28
Last Modified: 2012-05-11
Hey All,

I have given up on SBS 2011 POP3 and setting up Mx Logic. Inbound tested fine. However I am having issues with the smart connector. I have as the smarthost. However I am getting 451 4.4.0 Primary target IP address failed along with 421 4.2.1 unable to connect:

1) I can telnet a successful email
2) I have port 25 open
3) I have the external IP address setup on my firebox
4) I have my external ip address setup with Mcafee (mx logix)

Is it possibly a DNS issue?

Thanks again for the time. Our email is completely down so thanks again in advance for the help.
Question by:jgartrell
    LVL 7

    Expert Comment

    I can't resolve  That would probably be an issue.
    LVL 14

    Accepted Solution

    In case you haven't already done so, you need to tell MXLogic the IP address of your mail server(s)
    (poke around their web interface, and make sure the IP address of your mail server is in there in the right place)

    Another thing to check for outbound mail issues is your Send connectors.  To validate that your Send Connectors are configured properly, you can (temporarily) remove the smart host part of the configuration, and send directly to the internet - if your mail is delivered, your Send Connector is most likely fine.

    Also, since you are using MXLogic, you should at your firewall, permit port 25 traffic ONLY from MXLogic server IP addresses (they provide you with the range of addresses you need to permit).  


    Author Closing Comment

    Outgoing port number on send connector was 225 for the old email provider that was setup 5 years ago. Changed the port number to 25 in exchange cmd line and works great!!!!

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