diff --git a/phpBB/includes/functions.php b/phpBB/includes/functions.php
index 3a4a12777e..ed784405ac 100644
--- a/phpBB/includes/functions.php
+++ b/phpBB/includes/functions.php
@@ -3466,7 +3466,7 @@ function page_footer($run_cron = true)
 		'DEBUG_OUTPUT'			=> (defined('DEBUG')) ? $debug_output : '',
 		'TRANSLATION_INFO'		=> (!empty($user->lang['TRANSLATION_INFO'])) ? $user->lang['TRANSLATION_INFO'] : '',
 
-		'U_ACP' => ($auth->acl_get('a_') && $user->data['is_registered']) ? append_sid(CONFIG_ADM_FOLDER . 'index', false, true, $user->session_id) : '')
+		'U_ACP' => ($auth->acl_get('a_') && $user->data['is_registered']) ? append_sid(CONFIG_ADM_FOLDER . '/index', false, true, $user->session_id) : '')
 	);
 
 	// Call cron-type script
diff --git a/phpBB/install/install_install.php b/phpBB/install/install_install.php
index ff47c2c8a3..919f13dfa4 100755
--- a/phpBB/install/install_install.php
+++ b/phpBB/install/install_install.php
@@ -1944,7 +1944,7 @@ class install_install extends module
 			'TITLE'		=> $lang['INSTALL_CONGRATS'],
 			'BODY'		=> sprintf($lang['INSTALL_CONGRATS_EXPLAIN'], $config['version'], append_sid('install/index', 'mode=convert&language=' . $data['language']), '../docs/README.html'),
 			'L_SUBMIT'	=> $lang['INSTALL_LOGIN'],
-			'U_ACTION'	=> append_sid(CONFIG_ADM_FOLDER . '/index.' . PHP_EXT),
+			'U_ACTION'	=> append_sid(CONFIG_ADM_FOLDER . '/index'),
 		));
 	}