Error when accepting a calendar invite on Thunderbird: `Processing message failed. Status: 80004005.`

[biva]

Steps to reproduce

1. Receive a calendar invitation
2. Click on accept
3. Error happens: "Processing message failed. Status: 80004005."

Expected behaviour

The event should be added to the calendar and the answer sent to the organizer

Actual behaviour

I’m experiencing this on Mozilla Thunderbird 68.2.2. This problem happens when I receive an invitation. Sometimes, I see the HTML message (with the Nextcloud logo…). In this case, the error message 80004005 appears.

At some point, I don’t know why, the email looks different, with only one single table, with a blue row on top with the title of the event: when the email turns into this format, I can accept an invitation without any problem.

It happens if the person sending the invite is using Thunderbird, and is using a calendar on the same Nextcloud server. And it can also happen if the sender is not in my organisation. (using Outlook or Thunderbird, I don't know)

It might be related to the server managed scheduling mode: (on thunderbird, I have calendar.caldav.sched.enabled = false

In my config.php, I see:
'app_install_overwrite' =>
array (
0 => 'calendar',
),

Should I remove that?

I see related issues here:

• https://help.nextcloud.com/t/accepting-invitation-with-thunderbird-lightning-and-nextcloud-12-0-5/26791
• https://help.nextcloud.com/t/accepting-meeting-invite-fails-due-to-bad-outlook-formatting/55170 and the corresponding Github issue: ICS import fails - OPTION_FORGIVING should handle underscores #16679
• thunderbird/lightning not sending calendar notifications #8423
• https://bugzilla.mozilla.org/show_bug.cgi?id=1406402

Server configuration

• PHP 7.3.11-1+020191026.48+debian101.gbpf71ca0 (cli) (built: Oct 26 2019 14:20:37) ( NTS )
• mariadb Ver 15.1 Distrib 10.3.17-MariaDB, for debian-linux-gnu (x86_64) using readline 5.2
• Nextcloud 16.0.6

[biva]

I think this log could be related:
Sabre\DAV\Exception\BadRequest: Calendar object with uid already exists in this calendar collection.

/var/www/html/nextcloud/3rdparty/sabre/dav/lib/CalDAV/Calendar.php - line 201:

OCA\DAV\CalDAV\CalDavBackend->createCalendarObject("27", "d8hifi2s08t ... s", "BEGIN:VCALE ... n")

/var/www/html/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 1096:

Sabre\CalDAV\Calendar->createFile("d8hifi2s08t ... s", "BEGIN:VCALE ... n")

/var/www/html/nextcloud/3rdparty/sabre/dav/lib/DAV/CorePlugin.php - line 525:

Sabre\DAV\Server->createFile("calendars/e ... s", "BEGIN:VCALE ... n", null)

<<closure>>

Sabre\DAV\CorePlugin->httpPut(Sabre\HTTP\R ... "}, Sabre\HTTP\Response {})

/var/www/html/nextcloud/3rdparty/sabre/event/lib/EventEmitterTrait.php - line 105:

call_user_func_array([ Sabre\DAV\ ... "], [ Sabre\HTTP ... }])

/var/www/html/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 479:

Sabre\Event\EventEmitter->emit("method:PUT", [ Sabre\HTTP ... }])

/var/www/html/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 254:

Sabre\DAV\Server->invokeMethod(Sabre\HTTP\R ... "}, Sabre\HTTP\Response {})

/var/www/html/nextcloud/apps/dav/lib/Server.php - line 316:

Sabre\DAV\Server->exec()

/var/www/html/nextcloud/apps/dav/appinfo/v2/remote.php - line 35:

OCA\DAV\Server->exec()

/var/www/html/nextcloud/remote.php - line 163:

require_once("/var/www/ht ... p")

[biva]

After more investigation, it looks like the event can be accepted only if I manually sync the calendar.
Step to reproduce:

1. Receive the email: it is shown as an HTML page, with the Nextcloud button "Accept" in the middle
2. Click on "Accept" (not the Nextcloud button in the middle, but the Thunderbird button, top right)
3. Error message 80004005 appears
4. Sync Calendars in Thunderbird
5. Go back to the message: it is shown as the table mentioned above
6. Click on the "Accept" Thunderbird button → it works

It should work in step 2 above, I shouldn't be required to go up to step 6

[biva]

No idea? To give you more detail:

• Here is what I call the "HTML page": clicking on the Accept button (circled red) doesn't work (error message 80004005):
  

• And this is how it looks like after a manual sync (here, clicking on the Accept button (circled red) works).
  

[biva]

Does nobody meet the same issue? Any support?

[j-ed]

Does nobody meet the same issue? Any support?

That's exactly the point, this is the bug tracker for the development and NOT the Nextcloud help forum. Yo should search the forum first for any related issues, and if you cannot find an answer, you should raise your question there 😉

[biva]

@j-ed I already did, no answer there either https://help.nextcloud.com/t/accepting-invitation-with-thunderbird-lightning-and-nextcloud-12-0-5/26791/2?u=sisim
I created a new topic if it can bring it up: https://help.nextcloud.com/t/error-when-accepting-a-calendar-invite-on-thunderbird/65117

[biva]

Does nobody meet the same issue? I don't see any answer neither here nor on https://help.nextcloud.com/t/error-when-accepting-a-calendar-invite-on-thunderbird/65117 😢

[biva]

For the record, the workaround is to let Thunderbird manage the invitations:

• Go to your calendar on Thunderbird
• Right-click on your calendar name (on the left of the window)
• Choose Properties
• Check the box Prefer client-side email scheduling
• Click OK

I don't close the issue because I still think it's a bug: there should not be such issues between Nextcloud and Thunderbird, which is one of the most important open-source email/calendar software

[TooManyUsers63920]

Same issue here, but your workaround doesn't seem to work for me.

Double clicking the event in the calendar and selecting Accept does seem to work however.

Thunderbird 68.3.1
Lightning 68.3.1.1

I found other applications struggling with the same thing, i.e. DavMail to Exchange:
https://sourceforge.net/p/davmail/bugs/651/

"The cause of the error is Microsoft Exchange's Calendar attendant. It automatically processes the invitation and adds it to the calendar on the server-side. On the client side (Thunderbird), this change is not known because the calendar is not yet synchronized. As a result, the client tries to add an event that has already been added, hence the error."

It looks like exchange does the same thing as Nextcloud: it processs the event. If you then try to accept in Thunderbird before syncing it will fail. Sync first and the message will show the event has already been processed.

[0xphk]

Thanks @biva, the workaround in Thunderbird works for us.

Does anybody know if there is a similar option to set in Evolution Mail to get Invites accepted through mailclient?

[bobbolous]

Today I had the same issue.
Invitation from a Outlook Client via Microsoft Exchange Server.
Tried to accept/decline it with Thunderbird and various Nextcloud Calendars enabled.
Above fixes did not work. But I noticed all my calendars are connected to the same mail adress inside Thunderbird. Removed mail adress from all but one calendar, now it works.
In Thunderbird:
Right click on calendar -> properties -> Email: none (german: "keine").

Seems to me like a Thunderbird issue.