diff --git a/classes/local/outagelib.php b/classes/local/outagelib.php
index fa9a395..b7ceb2e 100644
--- a/classes/local/outagelib.php
+++ b/classes/local/outagelib.php
@@ -272,6 +272,7 @@ if ((time() >= {{STARTTIME}}) && (time() < {{STOPTIME}})) {
         header('Expires: Mon, 20 Aug 1969 09:23:00 GMT');
         header('Last-Modified: ' . gmdate('D, d M Y H:i:s') . ' GMT');
         header('Accept-Ranges: none');
+        header('X-Moodle-Maintenance: manager');
         if ((defined('AJAX_SCRIPT') && AJAX_SCRIPT) || (defined('WS_SERVER') && WS_SERVER)) {
             exit(0);
         }