diff --git a/classes/local/outagelib.php b/classes/local/outagelib.php
index 57a0e49..d5e9e9a 100644
--- a/classes/local/outagelib.php
+++ b/classes/local/outagelib.php
@@ -290,7 +290,9 @@ class outagelib {
 if ((time() >= {{STARTTIME}}) && (time() < {{STOPTIME}})) {
     define('MOODLE_INTERNAL', true);
     require_once($CFG->dirroot.'/lib/moodlelib.php');
-    require_once($CFG->dirroot.'/lib/classes/ip_utils.php');
+    if (file_exists($CFG->dirroot.'/lib/classes/ip_utils.php')) {
+        require_once($CFG->dirroot.'/lib/classes/ip_utils.php');
+    }
     if (!remoteip_in_list('{{ALLOWEDIPS}}')) {
         header($_SERVER['SERVER_PROTOCOL'] . ' 503 Moodle under maintenance');
         header('Status: 503 Moodle under maintenance');
diff --git a/tests/phpunit/local/outagelib_test.php b/tests/phpunit/local/outagelib_test.php
index d5ecf60..0e04866 100644
--- a/tests/phpunit/local/outagelib_test.php
+++ b/tests/phpunit/local/outagelib_test.php
@@ -289,7 +289,9 @@ class outagelib_test extends advanced_testcase {
 if ((time() >= 123) && (time() < 456)) {
     define('MOODLE_INTERNAL', true);
     require_once($CFG->dirroot.'/lib/moodlelib.php');
-    require_once($CFG->dirroot.'/lib/classes/ip_utils.php');
+    if (file_exists($CFG->dirroot.'/lib/classes/ip_utils.php')) {
+        require_once($CFG->dirroot.'/lib/classes/ip_utils.php');
+    }
     if (!remoteip_in_list('hey\'\"you
 a.b.c.d
 e.e.e.e/20')) {
@@ -331,7 +333,9 @@ EOT;
 if ((time() >= 123) && (time() < 456)) {
     define('MOODLE_INTERNAL', true);
     require_once($CFG->dirroot.'/lib/moodlelib.php');
-    require_once($CFG->dirroot.'/lib/classes/ip_utils.php');
+    if (file_exists($CFG->dirroot.'/lib/classes/ip_utils.php')) {
+        require_once($CFG->dirroot.'/lib/classes/ip_utils.php');
+    }
     if (!remoteip_in_list('127.0.0.1')) {
         header($_SERVER['SERVER_PROTOCOL'] . ' 503 Moodle under maintenance');
         header('Status: 503 Moodle under maintenance');