diff --git a/lib/navigationlib.php b/lib/navigationlib.php
index b2fdc65a7c1..432a120dad6 100644
--- a/lib/navigationlib.php
+++ b/lib/navigationlib.php
@@ -2584,6 +2584,10 @@ class global_navigation extends navigation_node {
     protected function load_courses_enrolled() {
         global $CFG, $DB;
         $sortorder = 'visible DESC';
+        // Prevent undefined $CFG->navsortmycoursessort errors.
+        if (empty($CFG->navsortmycoursessort)) {
+            $CFG->navsortmycoursessort = 'sortorder';
+        }
         // Append the chosen sortorder.
         $sortorder = $sortorder . ',' . $CFG->navsortmycoursessort . ' ASC';
         $courses = enrol_get_my_courses(null, $sortorder);