This change allows to hide the e-mails to guests. Requires editing a PHP file XenForo. In the file library/XenForo/BbCode/Formatter/Base.php ", search for: PHP: $email = XenForo_Helper_String::censorString($email); Add below: PHP: $visitor = XenForo_Visitor::getInstance();if (!isset($visitor['user_id']) || $visitor['user_id'] == 0) { $link = XenForo_Link::buildPublicLink("register"); return 'Merci de vous <a href="' . $link . '">inscrire/identifier</a> pour voir l\'adresse e-mail';} Save and rebuild the message cache