SmarterMail 15.2 does not try secondary MX?
Question asked by Chia Lin Yap - August 14, 2016 at 9:16 PM
Hi all,
I have a SmarterMail 15.2 acting as a SMTP gateway. Recently after upgrading it to 15.2, many users complained of bounced emails. The delivery log as below:
[2016.08.12] 11:22:42 [46462] Delivery started for at 11:22:42 AM
[2016.08.12] 11:22:46 [46462] Skipping spam checks: No local recipients
[2016.08.12] 11:22:49 [46462] Sending remote mail for
[2016.08.12] 11:22:49 [46462] Initiating connection to
[2016.08.12] 11:22:49 [46462] Connecting to (Id: 1)
[2016.08.12] 11:22:49 [46462] Binding to local IP (Id: 1)
[2016.08.12] 11:22:49 [46462] Connection to from succeeded (Id: 1)
[2016.08.12] 11:22:50 [46462] RSP: 421 Cannot connect to SMTP server (, connect error 10061
[2016.08.12] 11:22:50 [46462] CMD: QUIT
[2016.08.12] 17:24:50 [46462] Sending remote mail for
[2016.08.12] 17:24:50 [46462] Initiating connection to
[2016.08.12] 17:24:50 [46462] Connecting to (Id: 1)
[2016.08.12] 17:24:50 [46462] Binding to local IP (Id: 1)
[2016.08.12] 17:24:50 [46462] Connection to from succeeded (Id: 1)
[2016.08.12] 17:24:52 [46462] RSP: 421 Cannot connect to SMTP server (, connect error 10061
[2016.08.12] 17:24:52 [46462] CMD: QUIT
[2016.08.12] 21:24:59 [46462] Sending remote mail for
[2016.08.12] 21:24:59 [46462] Initiating connection to
[2016.08.12] 21:24:59 [46462] Connecting to (Id: 1)
[2016.08.12] 21:24:59 [46462] Binding to local IP (Id: 1)
[2016.08.12] 21:24:59 [46462] Connection to from succeeded (Id: 1)
[2016.08.12] 21:25:00 [46462] RSP: 421 Cannot connect to SMTP server (, connect error 10061
[2016.08.12] 21:25:00 [46462] CMD: QUIT
[2016.08.12] 21:25:05 [46462] Bounce email written to 40453224.eml
[2016.08.12] 21:25:05 [46462] Delivery for to has completed (Bounced)
[2016.08.12] 21:25:05 [46462] Delivery finished for at 9:25:05 PM    [id:40446462]
I verified that the recipient's MX isn't working. However, the recipient domain has a secondary MX which is working.
So I'm wondering, why is SmarterMail not trying secondary MX, primary MX failure? 
I have specified 9 retries and all of the retries only targeting the primary MX.
Please help, thank you!

5 Replies

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Has anyone facing the same issue, no? sob sob...
Hi Yap, it look like you have installed anti-virus and have setup filter out going SMTP. Base on your delivery log, your server were succeeded to the SMTP port . I believe is your internal anti-spam software have a SMTP proxy to filter all out going email causing the issue. You could try to disable your SMTP outgoing filtering on your anti-spam software.

[2016.08.12] 21:24:59 [46462] Connection to from succeeded (Id: 1)
[2016.08.12] 21:25:00 [46462] RSP: 421 Cannot connect to SMTP server (, connect error 10061
Hi DJ Won, thank you very much for the pointers.
I have checked again, but we really do not have any outgoing filter or anti-virus or anti-spam enabled.
If you try to telnet to the primary MX (, from other places (like, you'll see that the connection to the primary MX timed out. You actually got connected, but it eventually timed out.
Smartermail keeps on trying to connect to the primary MX, each time connected successfully, but eventually timed out. 
After the specified number of retries, Smartermail bounced the mail, and never attempted to try any of the secondary MX.
Hi DJ Won,
Yes I did try to telnet SMTP port 25 on my email server.
It got connected, but no welcome banner or anything, and later timed out.
Not only tried to telnet on my own server, I also tried with many other online telnet tools, all timed out.
I can safely say that is not working, and I'm afraid this situation is by design, that is they purposely put a broken MX as primary, in order to fight spam.
But why SmarterMail won't try the other MX, since the primary MX has timed out?
I'm having the same problem with as well. SmarterMail keeps on trying to send to primary MX, which timed out, but never try secondary MX
Andrea Rogers Replied
Employee Post
Hi Chia,
Sorry you're having this trouble! I've verified that SmarterMail should be trying the secondary MX records when the primary fails. Since this is not occurring in your installation, I would encourage you to reach out to our Support Department for further review. They will be able to log into your system and determine if this is a bug in the software or an issue specific to your installation. (Please keep in mind that if this issue is caused by a bug, your support ticket will be refunded.)
You have support tickets available on your account, so to submit this problem to support, please click on the Tickets button up above. Then click Start Ticket and choose the Support Department. You can also paste a link to this Community thread so they can see what details have been discussed and what you've already attempted to resolve this. 
Thank you!

Andrea Rogers
Communications Specialist
SmarterTools Inc.
(877) 357-6278

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