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We're having some intermediate issues with exim where some emails go through and then others get the 550 Cannot receive from specified address Error.

This is the guide we used to setup EXIM: https://sendgrid.com/docs/Integrate/Mail_Servers/exim.html

Now here's a exigrep from my exim_mainlogs file. Notice how there are a bunch of Completed QT=1s messages, but then randomly in the middle we have an Unauthenticated senders not allowed. It looks like sendgrid is processing some fine, but then errors out and kicks back the authentication error randomly, even though we're sending the correct credentials every time.

[root@dulce log]# exigrep "Re: Scanner and Printing System" exim_mainlog | more

2014-07-09 12:06:29 [14711] 1X4uO5-0003pH-2f <= jocelyn@haroldgarde.com H=cpe-74-71-193-253.nyc.res.rr.com ([192.168.0.6]) [74.71.193.253]:49427 I=[162.242.1
52.138]:25 P=esmtpsa X=TLSv1:AES128-SHA:128 CV=no SNI="dulce.45press.com" A=dovecot_plain:jocelyn@haroldgarde.com S=6560 M8S=0 id=D9563BCF-9506-4384-AD7E-CC6
7A204AE32@haroldgarde.com T="Re: Scanner and Printing System" from <jocelyn@haroldgarde.com> for tharvey@hallogram.com
2014-07-09 12:06:30 [14725] 1X4uO5-0003pH-2f => tharvey@hallogram.com F=<jocelyn@haroldgarde.com> P=<jocelyn@haroldgarde.com> R=send_via_sendgrid T=sendgrid_
smtp S=6701 H=smtp.sendgrid.net [198.37.144.212]:587 X=UNKNOWN:DHE-RSA-AES256-GCM-SHA384:256 CV=no DN="/OU=Domain Control Validated/CN=*.smtp.sendgrid.net" A
=sendgrid_login C="250 Delivery in progress" QT=1s DT=1s
2014-07-09 12:06:30 [14725] 1X4uO5-0003pH-2f Completed QT=1s

2014-07-09 13:25:31 [3099] 1X4vcZ-0000nz-HE <= jocelyn@haroldgarde.com H=cpe-74-71-193-253.nyc.res.rr.com ([192.168.0.6]) [74.71.193.253]:52929 I=[162.242.15
2.138]:25 P=esmtpsa X=TLSv1:AES128-SHA:128 CV=no SNI="dulce.45press.com" A=dovecot_plain:jocelyn@haroldgarde.com S=15739 M8S=0 id=D21395E7-6DB1-4F8A-8965-CE3
6FB1D2683@haroldgarde.com T="Re: Scanner and Printing System" from <jocelyn@haroldgarde.com> for tharvey@hallogram.com
2014-07-09 13:25:32 [3104] 1X4vcZ-0000nz-HE ** tharvey@hallogram.com F=<jocelyn@haroldgarde.com> P=<jocelyn@haroldgarde.com> R=send_via_sendgrid T=sendgrid_s
mtp: SMTP error from remote mail server after MAIL FROM:<jocelyn@haroldgarde.com> SIZE=17027: host smtp.sendgrid.net [198.37.144.225]: 550 Cannot receive fro
m specified address <jocelyn@haroldgarde.com>: Unauthenticated senders not allowed
2014-07-09 13:25:32 [3104] 1X4vcZ-0000nz-HE Completed QT=1s

2014-07-09 16:12:30 [18055] 1X4yEA-0004hD-4T <= jocelyn@haroldgarde.com H=cpe-74-71-193-253.nyc.res.rr.com ([192.168.0.6]) [74.71.193.253]:62575 I=[162.242.1
52.138]:25 P=esmtpsa X=TLSv1:AES128-SHA:128 CV=no SNI="dulce.45press.com" A=dovecot_plain:jocelyn@haroldgarde.com S=29598 M8S=0 id=7D4EC3BF-A30B-40EA-886B-FD
052DC2C5C2@haroldgarde.com T="Re: Scanner and Printing System" from <jocelyn@haroldgarde.com> for tharvey@hallogram.com
2014-07-09 16:12:31 [18061] 1X4yEA-0004hD-4T => tharvey@hallogram.com F=<jocelyn@haroldgarde.com> P=<jocelyn@haroldgarde.com> R=send_via_sendgrid T=sendgrid_
smtp S=30117 H=smtp.sendgrid.net [198.37.144.212]:587 X=UNKNOWN:DHE-RSA-AES256-GCM-SHA384:256 CV=no DN="/OU=Domain Control Validated/CN=*.smtp.sendgrid.net"
A=sendgrid_login C="250 Delivery in progress" QT=1s DT=1s
2014-07-09 16:12:31 [18061] 1X4yEA-0004hD-4T Completed QT=1s

2014-07-09 16:40:27 [23323] 1X4yf7-00064B-IP H=hallogram.com [128.121.218.188]:49302 I=[162.242.152.138]:25 Warning: "SpamAssassin as haroldga detected messa
ge as NOT spam (3.9)"
2014-07-09 16:40:27 [23323] 1X4yf7-00064B-IP <= tharvey@hallogram.com H=hallogram.com [128.121.218.188]:49302 I=[162.242.152.138]:25 P=esmtps X=TLSv1:EDH-RSA
-DES-CBC3-SHA:168 CV=no S=30591 M8S=0 id=036601cf9bb6$01ae7f80$050b7e80$@hallogram.com T="RE: Scanner and Printing System" from <tharvey@hallogram.com> for j
ocelyn@haroldgarde.com
2014-07-09 16:40:27 [23327] 1X4yf7-00064B-IP => jocelyn <jocelyn@haroldgarde.com> F=<tharvey@hallogram.com> P=<tharvey@hallogram.com> R=virtual_user T=virtua
l_userdelivery S=30711 QT=6s DT=0s
2014-07-09 16:40:27 [23327] 1X4yf7-00064B-IP Completed QT=6s

Sendgrid said that it's an issue with exim, but I'm not so sure since some of the emails work and others don't. Anyone have an idea about where to look?

Pika Supports Ukraine
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  • We get intermittent 550 issues as well with Sendgrid and Exim. Did you ever determine the cause and solution? – sa289 Oct 19 '15 at 18:16

1 Answers1

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Your provided information is very lean, not enough to accurately debug the problem, but I can make a few educated guesses and give you some places to look.

  1. Are you sure that the failed attemp was connecting to smtp.sendgrid.com:587? It's acting like your exim connected to port 25, and didn't use a user/pass to try to send, which sendgrid rejected.

  2. It very possibly is on their backend, where they are load balancing authentication across an array of LDAP servers, and one of them has stale information for your user, or one of them hits a resource limit and starts rejecting or timing-out new authentication attempts.

  3. Make sure that YOUR system isn't hitting resource limits and having failed lookups of the user/pass.

  4. Find out if anybody else is having periodic auth issues with smtp.sendgrid.com:587.

I'll add to this answer as you provide more debugging information in your original question, and hopefully we can work towards the ultimate solution.

Todd Lyons
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  • You're right about it using port 25... I would think that sendgrid would allow a connection to 25 as well, but I don't know enough about it to really understand where to look. Is it possible to force connections to 587 for users that try to connect to 25? Seems like people may be trying to use the non SSL/TLS connections... I will gladly provide any logs or information you need, just tell me where to look. I want to learn how to fix this, but just need a little direction :) –  Jul 11 '14 at 20:15