Google Calendar replies not recognized

[bentuna]

Steps to reproduce

1. Create an event and invite some external person who manages their calendar through Google Calendar.
2. Let the external person reply to your invitation directly via Google Calendar (without clicking in the Nextcloud invitation eMail that is sent to them).
3. See how you get an eMail from the persons Google account, telling you that they replied to your invitation.
4. See how in your Nextcloud calendar event, the participation status of the person is not updated.

Expected behavior

Nextcloud Calendar should notice these replies from external calendar servers and update the participation status.

In our experience, this is one of the main reasons for people to complain about Nextclouds incompatibilities regarding calendars.

Actual behavior

The replies from external calendar servers are not recognized and so the organizer of an event has no overview about external participation if someone did not click on the Nextcloud eMail link. And for the invited person it is not clear that they have to click the link, because they assume that they can reply using their calendar software they are always using.

Calendar app version

5.5.9

CalDAV-clients used

No response

Browser

No response

Client operating system

No response

Server operating system

No response

Web server

None

Database engine version

None

PHP engine version

None

Nextcloud version

31.0.12

Updated from an older installed version or fresh install

None

List of activated apps

Nextcloud configuration

Web server error log

Log file

Browser log

Additional info

No response

[SebastianKrupinski]

Hi @bentuna

Could you share the iMip ics file that is sent with me? You can sanitize the email addresses and names, but keep the rest exactly as is please.

[bentuna]

Hi @SebastianKrupinski, thank you for the quick response!

Do you mean the file from the Google eMail about the response? In that eMail, there are two attachments ("invite.ics" & Mail-Anhang.ics"), both with the same content (redacted organizer and attendee email and name of event):

BEGIN:VCALENDAR
PRODID:-//Google Inc//Google Calendar 70.9054//EN
VERSION:2.0
CALSCALE:GREGORIAN
METHOD:REPLY
BEGIN:VEVENT
DTSTART:20260108T090000Z
DTEND:20260108T100000Z
DTSTAMP:20251219T215010Z
ORGANIZER;CN=Benjamin Orgis:mailto:my@mail.com
UID:83FD50E2-4FB7-40E8-A17D-611367CD5D12
ATTENDEE;CUTYPE=INDIVIDUAL;ROLE=REQ-PARTICIPANT;PARTSTAT=TENTATIVE;X-NUM-GU
 ESTS=0:mailto:invitee@email.de
CREATED:20251219T191057Z
DESCRIPTION:
LAST-MODIFIED:20251219T215010Z
LOCATION:https://portal.101lab.it/call/xxxxxx
SEQUENCE:0
STATUS:CONFIRMED
SUMMARY:Redacted name of the event
TRANSP:OPAQUE
X-APPLE-CREATOR-IDENTITY:com.apple.calendar
X-APPLE-CREATOR-TEAM-IDENTITY:0000000000
BEGIN:VALARM
ACTION:DISPLAY
DESCRIPTION:This is an event reminder
TRIGGER:-P0DT0H5M0S
END:VALARM
BEGIN:VALARM
ACTION:DISPLAY
DESCRIPTION:This is an event reminder
TRIGGER:-P0DT0H10M0S
END:VALARM
END:VEVENT
END:VCALENDAR

[SebastianKrupinski]

@bentuna yes that is what I needed to see.

I don't see anything off with the REPLY, other then "PARTSTAT=TENTATIVE" this person replied with a tentative.

So here is some details, on how this works.

A) User must have the mail app configured.
B) User must have the organizer email address configured in their user profile. (which should be the same if sent from NC)
C) Administrator must turn on mail providers -> use users email (this forces the invitation to be sent from the user email account so that the reply comes back to the same account)
D) Cron needs to run and update the mail, and also process all the imip messages

If this still does not work correctly, are there any errors in the nextcloud.log?