diff --git a/lib/setup.php b/lib/setup.php
index 210bdeef5d2..b6f82c7f9bd 100644
--- a/lib/setup.php
+++ b/lib/setup.php
@@ -147,7 +147,7 @@ if (defined('BEHAT_SITE_RUNNING')) {
 // Normalise dataroot - we do not want any symbolic links, trailing / or any other weirdness there
 if (!isset($CFG->dataroot)) {
     if (isset($_SERVER['REMOTE_ADDR'])) {
-        header($_SERVER['SERVER_PROTOCOL'] . ' 503 Service Unavailable');
+        header($_SERVER['SERVER_PROTOCOL'] . ' 500 Internal Server Error ');
     }
     echo('Fatal error: $CFG->dataroot is not specified in config.php! Exiting.'."\n");
     exit(1);
@@ -155,13 +155,13 @@ if (!isset($CFG->dataroot)) {
 $CFG->dataroot = realpath($CFG->dataroot);
 if ($CFG->dataroot === false) {
     if (isset($_SERVER['REMOTE_ADDR'])) {
-        header($_SERVER['SERVER_PROTOCOL'] . ' 503 Service Unavailable');
+        header($_SERVER['SERVER_PROTOCOL'] . ' 500 Internal Server Error ');
     }
     echo('Fatal error: $CFG->dataroot is not configured properly, directory does not exist or is not accessible! Exiting.'."\n");
     exit(1);
 } else if (!is_writable($CFG->dataroot)) {
     if (isset($_SERVER['REMOTE_ADDR'])) {
-        header($_SERVER['SERVER_PROTOCOL'] . ' 503 Service Unavailable');
+        header($_SERVER['SERVER_PROTOCOL'] . ' 500 Internal Server Error ');
     }
     echo('Fatal error: $CFG->dataroot is not writable, admin has to fix directory permissions! Exiting.'."\n");
     exit(1);
@@ -170,7 +170,7 @@ if ($CFG->dataroot === false) {
 // wwwroot is mandatory
 if (!isset($CFG->wwwroot) or $CFG->wwwroot === 'http://example.com/moodle') {
     if (isset($_SERVER['REMOTE_ADDR'])) {
-        header($_SERVER['SERVER_PROTOCOL'] . ' 503 Service Unavailable');
+        header($_SERVER['SERVER_PROTOCOL'] . ' 500 Internal Server Error ');
     }
     echo('Fatal error: $CFG->wwwroot is not configured! Exiting.'."\n");
     exit(1);
diff --git a/lib/setuplib.php b/lib/setuplib.php
index 9dd220ffa51..da146429b41 100644
--- a/lib/setuplib.php
+++ b/lib/setuplib.php
@@ -2047,7 +2047,7 @@ class bootstrap_renderer {
         // In the name of protocol correctness, monitoring and performance
         // profiling, set the appropriate error headers for machine consumption.
         $protocol = (isset($_SERVER['SERVER_PROTOCOL']) ? $_SERVER['SERVER_PROTOCOL'] : 'HTTP/1.0');
-        @header($protocol . ' 503 Service Unavailable');
+        @header($protocol . ' 500 Internal Server Error');
 
         // better disable any caching
         @header('Content-Type: text/html; charset=utf-8');