diff --git a/lib/ext/Syncroton/Model/EmailMeetingRequest.php b/lib/ext/Syncroton/Model/EmailMeetingRequest.php
--- a/lib/ext/Syncroton/Model/EmailMeetingRequest.php
+++ b/lib/ext/Syncroton/Model/EmailMeetingRequest.php
@@ -78,7 +78,7 @@
             'dtStamp'                   => array('type' => 'datetime'),
             'endTime'                   => array('type' => 'datetime'),
             'globalObjId'               => array('type' => 'string'),
-            'instanceType'              => array('type' => 'datetime'),
+            'instanceType'              => array('type' => 'number'),
             'location'                  => array('type' => 'string'),
             'organizer'                 => array('type' => 'string'), //e-mail address
             'recurrenceId'              => array('type' => 'datetime'),
diff --git a/lib/kolab_sync_data_email.php b/lib/kolab_sync_data_email.php
--- a/lib/kolab_sync_data_email.php
+++ b/lib/kolab_sync_data_email.php
@@ -408,23 +408,21 @@
             $meeting['dtStamp'] = self::date_from_kolab($event['dtstamp'] ?? null);
             $meeting['endTime'] = self::date_from_kolab($event['end'] ?? null);
             $meeting['location'] = $event['location'] ?? null;
-
-            //TODO implement recurrences. We can't detect exceptions like this (don't know how), and the recurrences structure is different from event,
-            //so that also doesn't work like this.
-            // if (isset($event['recurrence']['EXCEPTIONS'])) {
-            //     $meeting['instanceType'] = Syncroton_Model_EmailMeetingRequest::TYPE_RECURRING_EXCEPTION;
-            //     $this->recurrence_from_kolab($collection, $event, $meeting);
-            // // } else if (isset($event['recurrence'])) {
-            // //     $meeting['instanceType'] = Syncroton_Model_EmailMeetingRequest::TYPE_RECURRING_SINGLE;
-            // //     $meeting['recurrenceId'] = set the date;
-            // } else if (isset($event['recurrence'])) {
-            //     $meeting['instanceType'] = Syncroton_Model_EmailMeetingRequest::TYPE_RECURRING_MASTER;
-            //     $this->recurrence_from_kolab($collection, $event, $meeting);
-            // } else {
-            //     $meeting['instanceType'] = Syncroton_Model_EmailMeetingRequest::TYPE_NORMAL;
-            // }
             $meeting['instanceType'] = Syncroton_Model_EmailMeetingRequest::TYPE_NORMAL;
 
+            if (!empty($event['recurrence_date'])) {
+                $meeting['recurrenceId'] = self::date_from_kolab($event['recurrence_date']);
+                if (!empty($event['status']) && $event['status'] == 'CANCELLED') {
+                    $meeting['instanceType'] = Syncroton_Model_EmailMeetingRequest::TYPE_RECURRING_EXCEPTION;
+                } else {
+                    $meeting['instanceType'] = Syncroton_Model_EmailMeetingRequest::TYPE_RECURRING_SINGLE;
+                }
+            } else if (!empty($event['recurrence'])) {
+                $meeting['instanceType'] = Syncroton_Model_EmailMeetingRequest::TYPE_RECURRING_MASTER;
+                // TODO: MeetingRequest recurrence is different that the one in Calendar
+                //     $this->recurrence_from_kolab($collection, $event, $meeting);
+            }
+
             // Organizer
             if (!empty($event['attendees'])) {
                 foreach ($event['attendees'] as $idx => $attendee) {