Updating a event sends "canceled" notification to participants

[schiessle]

Steps to reproduce

1. Create a calendar invitation, in my case I used the "appointment booking"-feature. But with regular invitation you should see the same effect
2. As the owner of the event, edit it (e.g. add a talk room to the location)
3. Check the mail account from the invited person

Expected behavior

The invited person gets an update of the appointment

Actual behaviour

The actual behavior depends on how I edit the event:

edit it with the Nextcloud calendar app

If I edit it with the Nextcloud calendar app in the browser no mail is send at all. So the participants never get notified about the changes

Edit it with Thunderbird 102.4.1

The result depends now on the Thunderbird calendar setting (right click on the calendar -> properties)

My default:

By default I tell Thunderbird that it should send invitation mails client-side because this way the recipient get a more "standard" invitation but not our html mail.

Surprisingly in this case a "cancel" mail from the Nextcloud server is triggered:

If I change the settings above and uncheck "prefer client-side email scheduling". No mail at all is send. Same as when I edit the event with the calendar app in the browser.

Calendar app version

4.1.0

CalDAV-clients used

Thunderbird 102.4.1

Browser

No response

Client operating system

Fedora

Server operating system

cloud.nextcloud.com

Web server

No response

Database engine version

No response

PHP engine version

No response

Nextcloud version

25.0.1

Updated from an older installed version or fresh install

No response

List of activated apps

No response

Nextcloud configuration

No response

Web server error log

No response

Log file

No response

Browser log

No response

Additional info

No response

[schiessle]

I just tried to edit the event wit acalendar+ (a Android calendar app). This triggers a new invitation mail from Nextcloud. Not perfect (because a "update" would be the perfect solution) but at least not a "cancel" mail or nothing at all.

[miaulalala]

I'm not at all sure why the Thunderbird stuff is leading to the cancel. Can you forward me that email please? I need to check the body of th mail.

[schiessle]

That's the email I get: https://cloud.nextcloud.com/s/WZxdfooERJKT9Lo

It is clearly a mail send by Nextcloud, even that I checked the option "prefer client-side email". I would expect that Thunderbird sends the update directly. Instead it seems to send something back to our server which triggers the "cancel" mail without removing the calendar entry.

Today I tried Evolution from Gnome. If I configure Evolution in the way that the mail client should send the mails directly Evolution sends a update correctly and doesn't trigger the "cancel" mail from our server.

Summary of my current tests:

1. Evolution with the option that it should send the mails by itself, :heavy_check_mark: works (all mails client side, no Nextcloud mails)
2. Evolution without the option that it should send the mails by itself, :boom: broken (no mail at all if I modify the event, would expect that Nextcloud sends the right update mail)
3. Thunderbird with the option that it should send the mails by itself, :boom: broken (something triggers the "cancel" mail from Nextcloud, no mail from Thunderbird)
4. Thundebird without the option that it should send the mails by itself, :boom: broken (no mail at all if I modify the event, would expect that Nextcloud sends the right update mail)
5. Nextcloud Calendar app, :boom: broken (no mail at all send when I modify the event)
6. ACalendar+ on Android, work somehow :boom: / :heavy_check_mark: (I get two mails from the Nextcloud sever, first "cancelled" for the original a event and than a new invitation for the modified one)

[miaulalala]

So looks like it is indeed a complete cancel:

Content-Type: text/calendar; method=CANCEL; name=event.ics
Content-Disposition: attachment; filename=event.ics
Content-Transfer-Encoding: 8bit

[kernstock]

We're seeing the same issue. Creates a lot of confusion. :grimacing:

[kernstock]

• Thunderbird with the option that it should send the mails by itself, boom broken (something triggers the "cancel" mail from Nextcloud, no mail from Thunderbird)

• Thundebird without the option that it should send the mails by itself, boom broken (no mail at all if I modify the event, would expect that Nextcloud sends the right update mail)

• Nextcloud Calendar app, boom broken (no mail at all send when I modify the event)

This.

[ichdasich]

Same behavior just encountered on a 26.0.1 with calendar app 4.3.3; Clients are Evolution [Handle invitations yourself(in evolution)] and CaldavSync for outlook [same setting].

This first occured with the upgrade to 4.3.3, iirc; So might there have been some changes there that now also trigger this for the formerly working state (see evolution)?

[yharroch]

Hi i’ve the same problem with an iphone synchronised with caldav. Every time I create and invite someone else, the event is automatically canceled within the hour. I’ve investigated many times in the logs or activity module. I didn’t found a clue. I’ve found similar topic on the help section of nextcloud.com. https://help.nextcloud.com/t/event-cancel-mail-is-sent-but-it-was-not-cancelled/167491/2 Probably a bug with a caldav function.

Let us know if there is some progress about this.

[DanielKnabl]

Same issue here. NC version 27.1.2 Calendar app version 4.5.3 Appointments app version 1.15.4 Android davX5 app version 4.3.11-gplay

I couldn't not reliably reproduce the behaviour. Nevertheless, several appointments have been cancelled from the participants perspective as they received cancellation emails. Looking at the calendar though, from both the android app and the nc app, the appointments are still confirmed. I'd love to keep the current setup, but if we can't fix the issue, I'm more or less forced to switch to a paid alternative. So, just as an option, would it be possible to pay you (developer/s) to fix the issue for me instead of buying a different product?

Thanks, best regards Daniel

[nlincke]

Has this been solved?

I had this problem a coupe of months ago and thought it was gone, but some people i have incited reported suddenly cancellations again...

[yharroch]

On my side, we changed our PCs and the user concerned by the bug changed is smartphone from Iphone to Android. The bug didn't happened since.

[fpaquet]

Same annoying problem here.

Nextcoud 29.0.8 PHP 29.0.8 A-Calendar synced with DAVx 4.4.2-gplay

Takes about 1-2 hours until new registered calendar event ist cancelled. All participants receive cancellation mails, but the owner of the event receives no email.

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As we can see from this ticket, it happens with Thunderbird, Evolution, iPhone, DAVx clients So the problem must be within nextcloud itself.