diff --git a/common/framework/router.php b/common/framework/router.php
index 3b68648eb..8bc39d8ae 100644
--- a/common/framework/router.php
+++ b/common/framework/router.php
@@ -363,7 +363,7 @@ class Router
 					$internal_url = self::_insertRouteVars($result, $args2);
 					return $args[$prefix_type] . ($internal_url ? ('/' . $internal_url) : '');
 				}
-				elseif ($args['act'] === $action_info->default_index_act && !count($args2))
+				elseif (isset($args['act']) && $args['act'] === $action_info->default_index_act && !count($args2))
 				{
 					self::$_route_cache[$rewrite_level][$keys_string] = '$' . $prefix_type . '$act:delete';
 					return $args[$prefix_type];