diff --git a/index.php b/index.php
index b11560c..f482609 100644
--- a/index.php
+++ b/index.php
@@ -9,6 +9,10 @@ if (isset($_SESSION['Firma']['ID']))
 }
 include "inc/config.php"; // die Konfigurationsdateien lesen
 require_once(__DIR__ . '/vendor/autoload.php');
+
+if (!defined('PREFIX')) {
+	define('PREFIX', '');
+}
 if ('Test' == PREFIX)
 {
 	exit();