nextcloud/server · warning · InvalidArgumentException

Calendar <$calendarId> doesn't support this function

Error message

Calendar <$calendarId> doesn't support this function

What it means

InvalidArgumentException thrown by occ dav:import-calendar (apps/dav/lib/Command/ImportCalendar.php:89) when the resolved calendar is not an OCA\DAV\CalDAV\CalendarImpl - i.e. it is a calendar contributed by an app through the calendar plugin/registry rather than a database-backed CalDAV calendar. Bulk import writes objects straight into the CalDAV backend, which only works for real CalDAV calendars.

Source

Thrown at apps/dav/lib/Command/ImportCalendar.php:89

		$errors = is_numeric($input->getOption('errors')) ? (int)$input->getOption('errors') : null;
		$validation = is_numeric($input->getOption('validation')) ? (int)$input->getOption('validation') : null;
		$supersede = $input->getOption('supersede');
		$showCreated = $input->getOption('show-created');
		$showUpdated = $input->getOption('show-updated');
		$showSkipped = $input->getOption('show-skipped');
		$showErrors = $input->getOption('show-errors');

		if (!$this->userManager->userExists($userId)) {
			throw new InvalidArgumentException("User <$userId> not found.");
		}
		// retrieve calendar and evaluate if import is supported and writeable
		$calendars = $this->calendarManager->getCalendarsForPrincipal('principals/users/' . $userId, [$calendarId]);
		if ($calendars === []) {
			throw new InvalidArgumentException("Calendar <$calendarId> not found");
		}
		$calendar = $calendars[0];
		if (!$calendar instanceof CalendarImpl) {
			throw new InvalidArgumentException("Calendar <$calendarId> doesn't support this function");
		}
		if (!$calendar->isWritable()) {
			throw new InvalidArgumentException("Calendar <$calendarId> is not writeable");
		}
		if ($calendar->isDeleted()) {
			throw new InvalidArgumentException("Calendar <$calendarId> is deleted");
		}
		// construct options object
		$options = new CalendarImportOptions();
		$options->setSupersede($supersede);
		if ($errors !== null) {
			$options->setErrors($errors);
		}
		if ($validation !== null) {
			$options->setValidate($validation);
		}
		$options->setFormat($format);
		$options->setCounts(true);

View on GitHub (pinned to ecdeb153ff)

Solutions

1. Import into a regular CalDAV calendar (one the user can edit in the Calendar app)
2. Create a fresh calendar as import target if needed
3. For app calendars, use the app's own import path

$calendars = $calendarManager->getCalendarsForPrincipal('principals/users/' . $uid, [$uri]);
if (!$calendars[0] instanceof \OCA\DAV\CalDAV\CalendarImpl) {
    throw new RuntimeException('Target is not an importable CalDAV calendar');
}

$isImportable = fn ($c): bool => $c instanceof \OCA\DAV\CalDAV\CalendarImpl;

When it happens

Trigger: occ dav:import-calendar alice <uri> ... where <uri> resolves to an ICalendar provided by an app (external/plugin calendar), not to CalendarImpl.

Common situations: Trying to import into read-only app calendars (e.g. birthday or app-generated calendars); custom apps registering ICalendar implementations expecting them to be importable.

Related errors

• Calendar <$calendarId> does not support exporting
• User <$userId> not found.
• Calendar <$calendarId> not found
• Calendar <$calendarId> is not writeable
• Calendar <$calendarId> is deleted

AI-assisted analysis of nextcloud/server@ecdeb153ff (2026-08-17). Data as JSON: /api/errors/0e8fc9a221597c05. Report an issue: GitHub.