Exim SMTP external connection failing after upgrade

[IanD]

I am using PHPMailer to connect to AOL to send emails, using the host smtp.aol.com:25

Prior to now, the script worked a charm. However, it now generates a 535 authentication error. I am struggling to trace how long this issue has been ongoing but I *think* it coincides with me upgrading to WHM 60.

I am 100% sure the username and password are correct and this untouched script was working, and now is not. I have also tried to hook it up to a Gmail account an got exactly the same outcome. On changing the settings to a mailbox on localhost, the emails successfully send.

I have tried to familiarise myself with the email sending process and one possible reason could be because the client EHLO sent is the website domain (domain1.com) whereas the data received back from the server hello is my server hostname (server.domain2.com). In my head this is a legitimate reason for an authentication failure, but maybe more goes on in the background (IP resolution?) that I am none the wiser about. What is noticeable is that on the successful send via localhost, the received hello is domain1.com as opposed to the server hostname, which is fuel in the fire of my theory.

Anyway, I am no expert, all I know is that it's one of these "suddenly stopped working" problems that I am 99% sure is nothing to do with the email provider, as I am using the exact same credentials in email clients, and the problems lies using multiple email providers, not just one.

One other thing to mention - and indeed this sent me on a wild goose chase for a while - is that I recently turned on AutoSSL to use https:// on all domains, and forced this usage using a rule in my generated httpd.conf file. I thought it might have been something to do with not being able to connect to an insecure port on a secure page but alas I believe this logic to be incorrect. Accessing through tls://smtp.aol.com:587 provided the same result.

Could there be anything in the release candidate of WHM 60 (I have just ungraded to the latest build of 13) that is the root of this issue?

Thanks

Ian

 

[cPanelMichael]

Hello @IanD,

Could you open a support ticket using the link in my signature so we can take a closer look? You can post the ticket number here so we can update this thread with the outcome.

Thank you.

 

[IanD]

Thanks Michael. Ticket number is 7855083.

 

[cPanelMichael]

Hello,

It looks like the support ticket is now resolved, however based on some of the dates of updates you provided in that ticket, I wanted to mention a case that was addressed in cPanel version 60.0.4 on October 13th, 2016:

Fixed case CPANEL-9214: Make the Apache->DomainTLS copy script ignore invalid certificates.

This may have have been the cause of the problem, based on the following quote from your initial message:

One other thing to mention - and indeed this sent me on a wild goose chase for a while - is that I recently turned on AutoSSL to use https:// on all domains, and forced this usage using a rule in my generated httpd.conf file. I thought it might have been something to do with not being able to connect to an insecure port on a secure page but alas I believe this logic to be incorrect. Accessing through tls://smtp.aol.com:587 provided the same result.

Invalid certificates in Domain TLS could have taken priority over valid service certificates before the server was updated with the fix referenced above.

Thank you.