diff --git a/admin/cron.php b/admin/cron.php
index 16c65f77744..9cc3083ac97 100644
--- a/admin/cron.php
+++ b/admin/cron.php
@@ -151,11 +151,18 @@
     mtrace('Removing expired enrolments ...', '');     // See MDL-8785
     $timenow = time();
     $somefound = false;
-    //The preferred way saves memory, dmllib.php
-    $rs_enrol = get_recordset_select('role_assignments',
-                                     'timeend > 0 AND timeend < '.$timenow,
-                                     $sort='',
-                                     'roleid, userid, contextid');
+    // The preferred way saves memory, dmllib.php
+    // find courses where limited enrolment is enabled
+    global $CFG;
+    $rs_enrol = get_recordset_sql("SELECT ra.roleid, ra.userid, ra.contextid
+        FROM {$CFG->prefix}course c
+        INNER JOIN {$CFG->prefix}context cx ON cx.instanceid = c.id
+        INNER JOIN {$CFG->prefix}role_assignments ra ON ra.contextid = cx.id
+        WHERE cx.contextlevel = '".CONTEXT_COURSE."'
+        AND ra.timeend > 0
+        AND ra.timeend < '$timenow'
+        AND c.enrolperiod > 0
+        ");
     mtrace($rs_enrol->RecordCount().' to delete');
     while ($oldenrolment = rs_fetch_next_record($rs_enrol)) {
         role_unassign($oldenrolment->roleid, $oldenrolment->userid, 0, $oldenrolment->contextid);