diff --git a/lang/en/error.php b/lang/en/error.php
index 7ad032cec31..9640c749ecb 100644
--- a/lang/en/error.php
+++ b/lang/en/error.php
@@ -432,6 +432,7 @@ $string['refoundtoorigi'] = 'Refunded to original amount: {$a}';
 $string['remotedownloaderror'] = 'Download of component to your server failed, please verify proxy settings, PHP cURL extension is highly recommended.<br /><br />You must download the <a href="{$a->url}">{$a->url}</a> file manually, copy it to "{$a->dest}" in your server and unzip it there.';
 $string['remotedownloadnotallowed'] = 'Download of components to your server isn\'t allowed (allow_url_fopen is disabled).<br /><br />You must download the <a href="{$a->url}">{$a->url}</a> file manually, copy it to "{$a->dest}" in your server and unzip it there.';
 $string['reportnotavailable'] = 'This type of report is only available for the site course';
+$string['requirecorrectaccess'] = 'Invalid url or port.';
 $string['requireloginerror'] = 'Course or activity not accessible.';
 $string['restorechecksumfailed'] = 'Some problem happened with the restore information stored in your session. Please check your PHP memory/DB package size limits. Restore stopped.';
 $string['restore_path_element_missingmethod'] = 'Restore method {$a} is missing. It must be defined by a developer.';
diff --git a/lib/setuplib.php b/lib/setuplib.php
index 51f8d827f42..fc786c4c669 100644
--- a/lib/setuplib.php
+++ b/lib/setuplib.php
@@ -356,7 +356,7 @@ function default_exception_handler($ex) {
     }
 
     if (is_early_init($info->backtrace)) {
-        echo bootstrap_renderer::early_error($info->message, $info->moreinfourl, $info->link, $info->backtrace, $info->debuginfo);
+        echo bootstrap_renderer::early_error($info->message, $info->moreinfourl, $info->link, $info->backtrace, $info->debuginfo, $info->errorcode);
     } else {
         try {
             if ($DB) {
@@ -370,7 +370,7 @@ function default_exception_handler($ex) {
             // so we just print at least something instead of "Exception thrown without a stack frame in Unknown on line 0":-(
             if (CLI_SCRIPT or AJAX_SCRIPT) {
                 // just ignore the error and send something back using the safest method
-                echo bootstrap_renderer::early_error($info->message, $info->moreinfourl, $info->link, $info->backtrace, $info->debuginfo);
+                echo bootstrap_renderer::early_error($info->message, $info->moreinfourl, $info->link, $info->backtrace, $info->debuginfo, $info->errorcode);
             } else {
                 echo bootstrap_renderer::early_error_content($info->message, $info->moreinfourl, $info->link, $info->backtrace, $info->debuginfo);
                 $outinfo = get_exception_info($out_ex);
@@ -761,6 +761,20 @@ function initialise_fullme() {
             if (!defined('NO_MOODLE_COOKIES')) {
                 define('NO_MOODLE_COOKIES', true);
             }
+            // The login/token.php script should call the correct url/port.
+            if (defined('REQUIRE_CORRECT_ACCESS')) {
+                $wwwrootport = empty($wwwroot['port'])?'':$wwwroot['port'];
+                $calledurl = $rurl['host'];
+                if (!empty($rurl['port'])) {
+                    $calledurl .=  ':'. $rurl['port'];
+                }
+                $correcturl = $wwwroot['host'];
+                if (!empty($wwwrootport)) {
+                    $correcturl .=  ':'. $wwwrootport;
+                }
+                throw new moodle_exception('requirecorrectaccess', 'error', '', null,
+                    'You called ' . $calledurl .', you should have called ' . $correcturl);
+            }
             redirect($CFG->wwwroot, get_string('wwwrootmismatch', 'error', $CFG->wwwroot), 3);
         }
     }
@@ -1497,7 +1511,7 @@ width: 80%; -moz-border-radius: 20px; padding: 15px">
      * @param string $debuginfo extra information for developers
      * @return string
      */
-    public static function early_error($message, $moreinfourl, $link, $backtrace, $debuginfo = null) {
+    public static function early_error($message, $moreinfourl, $link, $backtrace, $debuginfo = null, $errorcode = null) {
         global $CFG;
 
         if (CLI_SCRIPT) {
@@ -1525,6 +1539,7 @@ width: 80%; -moz-border-radius: 20px; padding: 15px">
                     $e->stacktrace = format_backtrace($backtrace, true);
                 }
             }
+            $e->errorcode  = $errorcode;
             @header('Content-Type: application/json; charset=utf-8');
             echo json_encode($e);
             return;
diff --git a/login/token.php b/login/token.php
index 9194de2df96..ad3b2c64cfa 100644
--- a/login/token.php
+++ b/login/token.php
@@ -22,6 +22,7 @@
  */
 
 define('AJAX_SCRIPT', true);
+define('REQUIRE_CORRECT_ACCESS', true);
 define('NO_MOODLE_COOKIES', true);
 
 require_once(dirname(dirname(__FILE__)) . '/config.php');