diff --git a/admin.php b/admin.php
--- a/admin.php
+++ b/admin.php
@@ -131,6 +131,8 @@ require_once('inc/admin.inc');
   function getMaxSaved()
   {
     $schedule_store = schedule_store_init();
+    if (empty($schedule_store))
+      return -1;
     return schedule_store_getmaxid($schedule_store);
   }