Secretary::provideAccessToMessage

private function provideAccessToMessage(int $messageId, int $calendarEventId): bool
{
	global $USER;
	$userId = $USER->GetID();

	return \Bitrix\Mail\Integration\Intranet\Secretary::provideAccessToMessage(
		$messageId,
		Message::ENTITY_TYPE_CALENDAR_EVENT,
		$calendarEventId,
		$userId
	);
}