Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    Cannot send mails using office365 smtp server

    Scheduled Pinned Locked Moved General pfSense Questions
    20 Posts 10 Posters 36.5k Views
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • arrmoA
      arrmo
      last edited by

      Hi,

      Port 587 is the specified port (and I confirmed, port 465 is not available / open). Interesting point about the password - thanks!

      I tried different settings (all port 587), here is what I get …

      1. Enable SMTP over SSL/TLS -> Error: could not connect to the host "smtp.office365.com": ?? (and fails very quickly)
      2. Enable STARTTLS -> Error: 504 5.7.4 Unrecognized authentication type (takes longer to fail)

      So the connection seems to be happening, but different failure modes? Thoughts?

      Thanks!

      1 Reply Last reply Reply Quote 0
      • N
        NOYB
        last edited by

        What do you get using port 587 with no encryption?

        1 Reply Last reply Reply Quote 0
        • N
          NOYB
          last edited by

          Did a little more digging and it seems that the pfSense notification system SSL/TLS setting only supports wrapper mode, with no way to disable it other than using Start TLS.

          So if the server, smtp.office365.com, in this case doesn't support ether wrapper mode or Start TLS, then there is no way to use it with encryption.

          1 Reply Last reply Reply Quote 0
          • arrmoA
            arrmo
            last edited by

            Hi,

            It's supposed to support Start TLS - at least from the digging I can do. So I admit, still a bit confused why it won't connect … :(.

            I have had issues in the past though (with other email servers, like Verizon), needing to use stunnel. Have you seen this before as well? I tried to install Stunnel, but get the error message "ERROR: No digital signature!". Is this something that needs to be updated / added in v2.2?

            Thanks!

            1 Reply Last reply Reply Quote 0
            • N
              NOYB
              last edited by

              From your earlier post it looks like the connection is successful with STARTTLS enabled.  But the authentication is failing.

              "2) Enable STARTTLS -> Error: 504 5.7.4 Unrecognized authentication type (takes longer to fail)"

              Google that error code and message string and you'll find lots of information that may point you in the right direction.

              1 Reply Last reply Reply Quote 0
              • arrmoA
                arrmo
                last edited by

                Hi,

                Yep, looked that error message up, and contacted (Microsoft) Exchange Online support. The one open question they have, that I can't seem to find … is pfSense using TLS v1.1 for the email send? They think that's the problem, but I can't confirm the version.

                Does anyone happen to know?

                Thanks!

                1 Reply Last reply Reply Quote 0
                • V
                  VoosW
                  last edited by

                  The problem is not exactly with Office 365 Mail servers - rather with Exchange (and potentially other mailservers as well):

                  While researching the issue that pfSense won't send using our Exchange 2010 Server I found the underlying cause for it.

                  pfSense (our version is 2.1.5-RELEASE, but I guess other versions are also affected) seems to support several Authentication mechanisms for SMTP (at least that's what I gathered from the various files), but it ALWAYS uses "PLAIN".
                  If the E-Mail-Server does not support "PLAIN", E-Mail-Notifications will fail - typically with "Authentication mechanism not supported".
                  Now - guess what … Exchange does support plaintext-logins when configured correctly, but only using the method "LOGIN" ...

                  The culprit is in File /etc/inc/notices.inc , Line 324:
                      // Use SMTP Auth if fields are filled out
                      if($config['notifications']['smtp']['username'] &&
                        $config['notifications']['smtp']['password']) {
                          $smtp->authentication_mechanism = "PLAIN";
                          $smtp->user = $config['notifications']['smtp']['username'];
                          $smtp->password = $config['notifications']['smtp']['password'];

                  if I change this line to
                  $smtp->authentication_mechanism = "LOGIN";
                  I can send e-mail-notifications via our  Exchange-Server. But I guess this will break Notifications for other mailservers.

                  IMHO there are two ways to fix this behaviour (sadly both beyond my pfSense/php-Knowledge):

                  1. get the list of supported auth-mechanisms from the server (after doing TLS if necessary - some servers offer plaintext-login only after a secue session was established) and "match" with local supported mechanisms (perhaps the smtp-class allows this already)?
                  2. allow the admin to select the auth-mechanism from a list of mechanisms supported by pfsense
                  1 Reply Last reply Reply Quote 0
                  • arrmoA
                    arrmo
                    last edited by

                    Hi,

                    Very cool finding - awesome! I'll give it a try (manual change), but also … why not start with 2), try 1) later? At least 2) would get things up and running.

                    Thanks!

                    1 Reply Last reply Reply Quote 0
                    • C
                      Cacique
                      last edited by

                      I had the same problem Authenticating but with Symantec Messaging Gateway (SMG). Changing PLAIN with LOGIN solve it. Thanks!

                      @VoosW:

                      The problem is not exactly with Office 365 Mail servers - rather with Exchange (and potentially other mailservers as well):

                      While researching the issue that pfSense won't send using our Exchange 2010 Server I found the underlying cause for it.

                      pfSense (our version is 2.1.5-RELEASE, but I guess other versions are also affected) seems to support several Authentication mechanisms for SMTP (at least that's what I gathered from the various files), but it ALWAYS uses "PLAIN".
                      If the E-Mail-Server does not support "PLAIN", E-Mail-Notifications will fail - typically with "Authentication mechanism not supported".
                      Now - guess what … Exchange does support plaintext-logins when configured correctly, but only using the method "LOGIN" ...

                      The culprit is in File /etc/inc/notices.inc , Line 324:
                          // Use SMTP Auth if fields are filled out
                          if($config['notifications']['smtp']['username'] &&
                            $config['notifications']['smtp']['password']) {
                              $smtp->authentication_mechanism = "PLAIN";
                              $smtp->user = $config['notifications']['smtp']['username'];
                              $smtp->password = $config['notifications']['smtp']['password'];

                      if I change this line to
                      $smtp->authentication_mechanism = "LOGIN";
                      I can send e-mail-notifications via our  Exchange-Server. But I guess this will break Notifications for other mailservers.

                      IMHO there are two ways to fix this behaviour (sadly both beyond my pfSense/php-Knowledge):

                      1. get the list of supported auth-mechanisms from the server (after doing TLS if necessary - some servers offer plaintext-login only after a secue session was established) and "match" with local supported mechanisms (perhaps the smtp-class allows this already)?
                      2. allow the admin to select the auth-mechanism from a list of mechanisms supported by pfsense
                      1 Reply Last reply Reply Quote 0
                      • arrmoA
                        arrmo
                        last edited by

                        Hi,

                        If you don't mind me asking - what are the rest of your settings (like port number, SSL/TLS or STARTTLS, etc.)? Still struggling a bit.

                        Thanks!!!

                        1 Reply Last reply Reply Quote 0
                        • arrmoA
                          arrmo
                          last edited by

                          Got it working! Issue was STARTTLS (and save before Test).

                          Thanks!

                          1 Reply Last reply Reply Quote 0
                          • A
                            andygorze
                            last edited by

                            This also fixed my issue, many thanks.

                            1 Reply Last reply Reply Quote 0
                            • C
                              creiglee
                              last edited by

                              for this issue I added my account via POP3 and SMTP in outlook 2016 it works fine and also I test it via power shell and It works fine too.

                              1 Reply Last reply Reply Quote 0
                              • B
                                bethelcolonyit
                                last edited by

                                E-Mail server: smtp.office365.com
                                SMTP Port of E-Mail server: 587
                                Connection timeout to E-Mail server: blank
                                Secure SMTP Connection: unchecked
                                From e-mail address: user@example.com
                                Notification E-Mail address: user@example.com
                                Notification E-Mail auth username (optional): user@example.com
                                Notification E-Mail auth password: userpassword
                                Notification E-Mail auth mechanism: Login
                                Send Test
                                Save after successful test

                                V 1 Reply Last reply Reply Quote 2
                                • V
                                  vishal.mhatre2310 @bethelcolonyit
                                  last edited by

                                  @bethelcolonyit. Helped in big way. Thank you so much for the poast

                                  1 Reply Last reply Reply Quote 0
                                  • S
                                    SteveITS Galactic Empire
                                    last edited by

                                    I know this is old but it was a top search result.

                                    The good news, there are 3 methods:
                                    https://docs.microsoft.com/en-us/exchange/mail-flow-best-practices/how-to-set-up-a-multifunction-device-or-application-to-send-email-using-microsoft-365-or-office-365

                                    The bad news: the purple note in section 1 (info on using a login and password) on that page:
                                    "This option is not compatible with Microsoft Security Defaults or multi-factor authentication (MFA). If your environment uses Microsoft Security Defaults or MFA, we recommend using Option 2 or 3 below.

                                    You must also verify that SMTP AUTH is enabled for the mailbox being used. See Enable or disable authenticated client SMTP submission (SMTP AUTH) in Exchange Online for more information."

                                    Pre-2.7.2/23.09: Only install packages for your version, or risk breaking it. Select your branch in System/Update/Update Settings.
                                    When upgrading, allow 10-15 minutes to restart, or more depending on packages and device speed.
                                    Upvote 👍 helpful posts!

                                    1 Reply Last reply Reply Quote 0
                                    • First post
                                      Last post
                                    Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.