diff --git a/server/core/Plugin_Api.php b/server/core/Plugin_Api.php
index 89f82fb..c2a9041 100644
--- a/server/core/Plugin_Api.php
+++ b/server/core/Plugin_Api.php
@@ -2,7 +2,7 @@
 
 //Init plugin directory
 if (!defined('PLUGINS_DIR')) {
-    define('PLUGINS_DIR', RCUBE_INSTALL_PATH . 'plugins/');
+    define('PLUGINS_DIR', INSTALL_PATH . 'plugins/');
 }
 
 class plugin_api{