private function buildErrorMailBody($error, PhabricatorMetaMTAReceivedMail $mail)
    {
        $original_body = $mail->getRawTextBody();
        $main_body = <<<EOBODY
Your request failed because an error was encoutered while processing it:

  ERROR: {$error}

  -- Original Body -------------------------------------------------------------

  {$original_body}

EOBODY;
        $body = new PhabricatorMetaMTAMailBody();
        $body->addRawSection($main_body);
        $body->addReplySection($this->getReplyHandlerInstructions());
        return $body->render();
    }