diff --git a/actions/shownotice.php b/actions/shownotice.php
index 7805242379..2ede559e26 100644
--- a/actions/shownotice.php
+++ b/actions/shownotice.php
@@ -19,7 +19,7 @@
 
 if (!defined('LACONICA')) { exit(1); }
 
-require_once(INSTALLDIR.'lib/stream.php');
+require_once(INSTALLDIR.'/lib/stream.php');
 
 class ShownoticeAction extends StreamAction {