There are several entries in the forum about notifications or alerts not being sent to the assigned Agent when a user has replied to a ticket. I've gone through all of the forum topics about it but found no solution to the problem I'm seeing since we updated osTicket from 1.09 to 1.18.

Since I was uncertain to which exact existing topic this would fit in, I thought to start a new topic as I might also have found the root cause. I will describe.

The problem:
When a user replies to a ticket via email, the reply is correctly added to the ticket, but most of the times no alert is sent to the assigned Agent, so the agent is not aware that a reply was received.

Tests done
I've done extensive testing and have found out that it has to do with the email client the user is using to send out their reply. I created a ticket for a test user being myself (with a @live.nl email address, not being the addresses used within the ticket system whatsoever!). That user is "Donald Duck". The user created a ticket and I answer to the ticket as the Agent in osTicket. User receives the answer. When user replies via email, using a simple email app on the Android phone (Bluemail in this case) the reply is correctly received in osTicket AND an alert it sent to the Agent.
However, when the user replies from the SAME @live.nl email address configured in MS Outlook, the reply is again correctly added to the ticket BUT NO ALERT is sent to the agent.
When the user replies using the link in the bottom of any ticket response, so not by sending an email but directly entering it into osTicket, the alert is also successfully sent to the agent.

I've already had a close look at the email headers of both emails and could not find any entries in the headers as listed in class.filter.php lines 903-915 such as suggested by @KevinTheJedi in several Forum topics. So, I'm in the blind about why the reply from user sent from Outlook is not triggering an alert to the agent while it does when the email is sent with another email client. I will attach both headers as replies hereunder (I have anonymized the email addresses within them). (not sure how to upload these, forum rejects .TXT files are not allowed, so I posted them as replies, hope that is ok)

Settings screenshots



    HansAlbers

    Header from email sent from Bluemail client on Android phone
    Response added to ticket AND alert successfully sent to Agent

    Delivered-To: thecompanyemail@gmail.com
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From: Hans Albers <donaldduck@live.nl>
To: "thecompanyemail@gmail.com" <thecompanyemail@gmail.com>
Subject: RE: Test ticket DD [#6322519]
Thread-Topic: Test ticket DD [#6322519]
Thread-Index: AQHbKfnw14m2KBd1D06gnVQJuotbEbKdoGWA
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      Response added to ticket but no alert to Agent

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From: Hans Albers <donaldduck@live.nl>
To: "thecompanyemail@gmail.com" <thecompanyemail@gmail.com>
Subject: RE: Test ticket DD [#6322519]
Thread-Topic: Test ticket DD [#6322519]
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Date: Tue, 29 Oct 2024 12:01:13 +0000
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        HansAlbers

        In the scenario where you don't get the alert, is the User replying directly to an alert/reply sent from the system? Or are they responding to their original email?

        Cheers.

            KevinTheJedi They reply to the last reply from the system (which includes the ticket# in the email subject) as sent out by the agent. This is also what I did when I was reproducing the issue.

                There is not in the case of my test. Both replies are replies to the same response from the agent. BUT: The first reply from the user was using Outlook and did not trigger an alert, while the second reply was 12 minutes later from Bluemail and it DID trigger an alert.

                Thanks!!!

                  I consulted a colleague who knows about pHp programming and we are not 100% if this is what you mean with dump, but this is what we added in class.ticket.php after line 3195 :

                  $ticket->onMessage($message, ($autorespond && $alerts), $reopen); //must be called b4 sending alerts to staff.
                  // debug alerts by c
                  $log = sprintf(__('debug message: %s'), $message);
                  $ost->logDebug(
                  sprintf( __('debug autorespond: %s'), $autorespond),
                  $log
                  );
                  $ost->logDebug(
                  sprintf( __('debug alerts: %s'), $alerts),
                  $log
                  );

                  Which caused these two entries in the log:


                  By the looks of it those variables seem to carry other data than just true or false.

                  Thanks again!

                    HansAlbers

                    Apparently your changes are not correct as it’s logging the message and not the needed variables. By dump I meant a simple var_dump($alerts, $autorespond);. Then run the cron command manually via the server’s CLI so you can see the output.

                    Cheers.

                      We now inserted var_dump($alerts, $autorespond); as you wrote and ran the cron manually which gave this output:
                      (when the reply from user was sent from Outlook email client which does not trigger an alert to the agent as stated before)

                      $ sudo php ./cron.php
                      bool(true)
                      bool(false)
                      So it seems that alerts=true, autorespond=false.

                      Then we ran the cron again after sending an email reply from user from Bluemail on Android phone to the same ticket, which does trigger an alert to the agent, and in this case the output was:

                      Both replies (the first one using Outlook, 2nd one using Bluemail) were replies to the exact same response email sent from osTicket to the user. Only the 2nd reply using Bluemail caused the alert to be sent.
                      I'm really wondering if something in the email header coming from Outlook messes things up. The thing is, I have no control over what email client customers are using. Most of them do use Outlook I'm afraid.

                      Any ideas? Many thanks!

                        HansAlbers

                        Yea, so now you need to track the $autorespond variable back to where it's being set to false. Then you will know what the cause is; likely the headers or something. If it's not something you can control then you would need to modify the codebase to your liking.

                        Cheers.

                          We have already debugged the codepieces lines 3186-3193 and our conclusion is that $vars['autorespond'] must be gotten set to false somewhere but we have no clue where and why.
                          We did not have this issue in the old v.1.09 osTicket so I'm wondering if there is a bug, also since I've seen many other entries in the forum complaining no alerts are getting sent out to agents for unknown reasons?

                          Many thanks, Hans

                          When I close the ticket and then have the user send a reply from outlook, the ticket even gets re-opened and reply is inserted in the ticket but no alert to agent.

                            HansAlbers

                            Once you find where it's being set to false we can better look into this. Since I can't replicate this I need an example to go on.

                            Cheers.

                              After commenting out lines 3191 and 3192 osTicket is sending alerts to agents regardless if reply was sent using the Outlook email client.

                              elseif ($autorespond && isset($vars['autorespond']))
                              $autorespond = $vars['autorespond'];
                              In the entire code I cannot find anything that sets $vars['autorespond'] to false. Some hints about in which direction I should be searching would be appreciated, as to what mechanism sets it.

                              BTW I found another thread where more or less the same issue is being discussed around 2 yrs ago.
                              https://forum.osticket.com/d/100969-osticket-intermittently-alerts-assigned-user/38

                              Thanks!

                              More searching delivered:

                              which is where $vars['autorespond'] is set to NOT isset($mailinfo['passive']).

                              And @mailinfo['passive'] is set here:

                              Unfortunately I have no idea how this further works and what it means. But apparently there is something with this passive threading thingy.

                              Hope this rings a bell for you. I've seen a similar Forum entry that is talking about the same, I believe.

                              Cheers, Hans

                                HansAlbers

                                Ah, yes. So "passive" means passive threading. Passive threading occurs when the system couldn't find a References header, In-Reply-To header, Message-ID header, or Message-ID in the body of the email that was generated by the helpdesk itself (ie. one that it was able to decode). However it could find one of those headers that matches an existing thread entry in the database so the system will silently thread it through. osTicket will only send alerts when one of the aforementioned headers contain a header it can decode (ie. one that was sent by the system). This is why I originally asked if they are responding to one of their previous emails vs an email sent from an Agent or an alert from the system; as this matters greatly.

                                But what's weird is that in your header examples above for the one that does work I don't see a header that the system would be able to decode so I'm not sure how that one is working. Are you certain you didn't modify the header examples above? Like change an email for a different one or change some of the references, etc.?

                                Cheers.

                                  Well, in all my testing, replies from user were a direct reply to the last response sent by agent from osTicket and our real customers are doing so as well, yet our agents hardly get alerts about such replies.

                                  In the scenario where they do not reply to the ticket-response, but to their original email that "generated the ticket" for each of such replies a new ticket is created because the ticket# is not in the subject line. But that is acceptable and understandable. But that is not the scenario that is causing us headaches now.