Have you set the following option in sogo.conf?
SOGoAppointmentSendEMailNotifications = YES;

seem's to be similar https://bugs.sogo.nu/view.php?id=5608

Hi, could you please try with the last nightly version ?

tested with nightly version 5.7.1.20220925-1 (on debian 11) : delegating an event invite, e-mail is triggered to attendee ( placed in calendar and e-mail)

maybe an hint: invite a person via aliased e-mail address (which is not in result set of user source of sogo) ->
user can add the invitation to the calendar, but no e-mail is triggered neither the person is able to make a decision - no accept, no decline option in webui.....) ......

@MrT2020
Of course this will not work!
SOGo has to know that the email address used in the invite belongs to the logged in user.
Else it can not recognize, that the user is actually invited and therefore meant to answer.

of course - i understand thx - was just a hint , why notification was n't triggered for "bahnkonzept " (poorly phrased by me ;-) )

SOGoAppointmentSendEMailNotifications = YES;

ist set in sogo.conf

Unfortunately we can't test the latest nightly builds to check whether this issue is solved or not.

Maybe some clarification:

• external user sends invitation to SoGO user1
• SoGO user1 receives the invitation e-mail and does not press the accept button but uses the delegation feature SoGO offers in the webmail view
• user1 delegates to user2, who is part of the same SoGO instance as user1
• after delegation:
  -- user2 has calendar item for the invitation with "unanswered" status (as expected)
  -- user1 has calendar item for the invitation (as expected)
  -- external user gets an e-mail that user1 has delegated the invitation to user2 (as expected)
  -- but: user2 never gets an e-mail notification that an/the invitation was delegated to him (not as expected); although user2 should receive such an e-mail with the known buttons ("accept", "decline", ...)

If the last point is solved by the latest changes, then the issue is solved from our point of view.

@bahnkonzept: can confirm your issue

nightly buildversion /debian11: 5.7.1.20221006-1

... seems to be fixed; I just tried and see that the person where an appointment was delegated get's an email now. Ticket might be closed.