diff --git a/inc/caldav-REPORT-sync-collection.php b/inc/caldav-REPORT-sync-collection.php
index 6a6b67bd..f0a12cad 100644
--- a/inc/caldav-REPORT-sync-collection.php
+++ b/inc/caldav-REPORT-sync-collection.php
@@ -31,7 +31,7 @@ if ( $sync_level == DEPTH_INFINITY ) {
 }
 
 $sync_tokens = $xmltree->GetPath('/DAV::sync-collection/DAV::sync-token');
-$sync_token = $sync_tokens[0]->GetContent();
+if ( isset($sync_tokens[0]) ) $sync_token = $sync_tokens[0]->GetContent();
 if ( !isset($sync_token) ) $sync_token = 0;
 $sync_token = intval(str_ireplace('data:,', '', $sync_token ));
 dbg_error_log( 'sync', " sync-token: %s", $sync_token );