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SBS 2011 and Mx Logic Setup send connector error 451 4.2.1

jgartrell asked
Medium Priority
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 domain.com.outbound15.mxlogic.net 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.
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I can't resolve outbound15.mxlogic.net.  That would probably be an issue.
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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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