diff --git a/web/skins/classic/views/js/login.js.php b/web/skins/classic/views/js/login.js.php
index e18fce8dc..1df69c5b4 100644
--- a/web/skins/classic/views/js/login.js.php
+++ b/web/skins/classic/views/js/login.js.php
@@ -1 +1 @@
-var failed = <?php echo $_SESSION['loginFailed']?'true':'false' ?>;
+var failed = <?php echo isset($_SESSION['loginFailed'])?'true':'false' ?>;