Problem with STMP for Outlook 2012, 2013 for windows and in outlook for mac2019 - Bug Report

When I try o send emails with those outlooks gives me an error 17895. I have tested: port 25 same issue, 485 same issue, 587 same issue, I had the Microsoft engineers for a day looking at it with no luck, I have search 4 easy for any hint with no luck, and asked help for this for support in my server with no luck.

The questions is any other mail apps work perfectly well, if I use other linux server for sending with those messages in outlook (my Channel) works perfect.

Can you help?

Mail log

Nov 29 07:52:40 localhost postfix/submission/smtpd[23338]: connect from unknown[88.98.aaa.aaa]
Nov 29 07:52:40 localhost postfix/submission/smtpd[23338]: lost connection after EHLO from unknown[88.98.aaa.aaa]
Nov 29 07:52:40 localhost postfix/submission/smtpd[23338]: disconnect from unknown[88.98.aaa.aaa] ehlo=2 starttls=1 commands=3
Nov 29 07:52:40 localhost postfix/submission/smtpd[24749]: connect from unknown[88.98.aaa.aaa]
Nov 29 07:52:41 localhost postfix/submission/smtpd[24749]: lost connection after EHLO from unknown[88.98.aaa.aaa]
Nov 29 07:52:41 localhost postfix/submission/smtpd[24749]: disconnect from unknown[88.98.aaa.aaa] ehlo=2 starttls=1 commands=3
Nov 29 07:52:41 localhost postfix/submission/smtpd[23338]: connect from unknown[88.98.aaa.aaa]

Thanks in advance

Could not post in bug report

You just just need to add auth_mechanisms to /etc/dovecot/dovecot.conf and restart dovecot.

auth_mechanisms = plain login

Thanks a lot!!! i did in all the other files with no luck. Working perfectly!!

In what part of the content of dovecot.conf do I add it?

There should be already a auth_mechanisms in there.

It wasnt, Cesarin, use any line!

Thanks today I try it and notice if it worked.

i assure you it worked!!

It didn’t work out.

When I set up Outlook in POP3 with SSL it works perfect
When I set up Outlook in POP3 without SSL it doesn’t work

It is a problem with the cyberpanel, because with PLESK it works perfectly, with CPanel it also works very well.

CyberPanel 2.0

Outlook 365 MacOS

• Outlook on IMAP + SSL - work perfectly
• Outlook on IMAP - SSL - work perfectly
• Outlook on POP + SSL - Unable to sign in. Check your credentials and try again.
• Outlook on POP - SSL - Unable to sign in. Check your credentials and try again.

Mail App OSX

• POP3 Automatic config - OK
  Warning - Mail cannot send your password securely to the server. You can continue without a secured password, which could put your password at risk. But in the final works.

Thunderbird for OSX

• POP3 connection OK
  Warning about insecure mail connection on both IMAP & POP; SMTP ok

Definitely it’s a specific problem with Outlook 365 on POP3.
Please investigate and come with a solution.

Type your comment> @Numeriku said:

You just just need to add auth_mechanisms to /etc/dovecot/dovecot.conf and restart dovecot.

auth_mechanisms = plain login

By default only PLAIN mechanism is enabled.
To use more, edit your /etc/dovecot/conf.d/10-auth.conf and set:

auth_mechanisms = plain login

I just realised that our /etc/dovecot/dovecot.conf doesn’t have the include to read the conf.d files.
Numeriku was right, put the “auth_mechanisms = plain login” in /etc/dovecot/dovecot.conf

Anyway, that should be included by default in the install of CP to avoid issues