Mattermost, Inc.

Auth failure on OpenSMTPD

This is probably something I have done and my brain shut down an hour ago. When setting up SMTP according to http://docs.mattermost.com/install/smtp-email-setup.html, I click Test Connection and this error message appears.
Connection unsuccessful: Failed to authenticate on SMTP server - 535 Authentication failed

My Mattermost log.
[2016/05/24 02:40:39 EDT] [EROR] /api/v3/admin/test_email:SendMail code=500 rid=xanjdn9bdtfxientf79xadtdby id=b63kfq4bdfrquea17wxc85nu4o ip=MY_IP Failed to authenticate on SMTP server [details: 535 Authentication failed]

My OpenSMTPD log.
May 24 02:40:37 mail smtpd[956]: smtp-in: New session ffffffffd7704cfb from host MATTERMOST_IP [MATTERMOST_IP] May 24 02:40:37 mail smtpd[956]: smtp-in: Started TLS on session ffffffffd7704cfb: version=TLSv1/SSLv3, cipher=ECDHE-RSA-AES128-GCM-SHA256, bits=128 May 24 02:40:39 mail smtpd[956]: smtp-in: Authentication failed for user mattermost@EXAMPLE.com on session ffffffffd7704cfb May 24 02:40:39 mail smtpd[956]: smtp-in: Failed command on session ffffffffd7704cfb: "AUTH [...]" => 535 Authentication failed May 24 02:40:39 mail smtpd[956]: smtp-in: Failed command on session ffffffffd7704cfb: "*" => 500 Command unrecognized May 24 02:40:39 mail smtpd[956]: smtp-in: Closing session ffffffffd7704cfb

Everything is pointing to incorrect password or user. I have double and triple checked I can log into my server using these credentials. Please point me in the right direction.

Thanks

Hi @nuclearcanary,

it seems to me that the problem is related to OpenSMTPD based on this. Can you confirm that? maybe try and update OpenSMTPD?

Thank you. I will certainly try that. I had an auth error the other day when accessing through Nylas N1, but they upgraded the client and it worked. I was assuming that is was a bug in the underlying Go SMTP code. I am running it on Ubuntu 14.04, So I will try to find a PPA or compile from source. I will report back what I find out.