diff --git a/admin/cron.php b/admin/cron.php
index ff19e6f33c3..5e9ea7c8077 100644
--- a/admin/cron.php
+++ b/admin/cron.php
@@ -141,11 +141,13 @@
     
         /// Delete users who haven't confirmed within required period
 
-        $oneweek = $timenow - ($CFG->deleteunconfirmed * 3600);
-        if ($users = get_users_unconfirmed($oneweek)) {
-            foreach ($users as $user) {
-                if (delete_records('user', 'id', $user->id)) {
-                    mtrace("Deleted unconfirmed user for ".fullname($user, true)." ($user->id)");
+        if (!empty($CFG->deleteunconfirmed)) {
+            $oneweek = $timenow - ($CFG->deleteunconfirmed * 3600);
+            if ($users = get_users_unconfirmed($oneweek)) {
+                foreach ($users as $user) {
+                    if (delete_records('user', 'id', $user->id)) {
+                        mtrace("Deleted unconfirmed user for ".fullname($user, true)." ($user->id)");
+                    }
                 }
             }
         }
@@ -155,11 +157,13 @@
 
         /// Delete users who haven't completed profile within required period
 
-        $oneweek = $timenow - ($CFG->deleteunconfirmed * 3600);
-        if ($users = get_users_not_fully_set_up($oneweek)) {
-            foreach ($users as $user) {
-                if (delete_records('user', 'id', $user->id)) {
-                    mtrace("Deleted not fully setup user $user->username ($user->id)");
+        if (!empty($CFG->deleteunconfirmed)) {
+            $oneweek = $timenow - ($CFG->deleteunconfirmed * 3600);
+            if ($users = get_users_not_fully_set_up($oneweek)) {
+                foreach ($users as $user) {
+                    if (delete_records('user', 'id', $user->id)) {
+                        mtrace("Deleted not fully setup user $user->username ($user->id)");
+                    }
                 }
             }
         }