diff --git a/phpBB/includes/acp/acp_main.php b/phpBB/includes/acp/acp_main.php
index ca3b885e11..6e44d931d2 100644
--- a/phpBB/includes/acp/acp_main.php
+++ b/phpBB/includes/acp/acp_main.php
@@ -639,7 +639,7 @@ class acp_main
 		}
 
 		// Warn if install is still present
-		if (!defined('IN_INSTALL') && !$phpbb_container->getParameter('allow_install_dir') && file_exists($phpbb_root_path . 'install') && !is_file($phpbb_root_path . 'install'))
+		if (!$phpbb_container->getParameter('allow_install_dir') && file_exists($phpbb_root_path . 'install') && !is_file($phpbb_root_path . 'install'))
 		{
 			$template->assign_var('S_REMOVE_INSTALL', true);
 		}