core/lexicon/en/mail.inc.php
<?php
/**
* Mail English lexicon topic
*
* @language en
* @package modx
* @subpackage lexicon
*/
$_lang['mail_err_address_ns'] = 'You must provide an email address to send to.';
$_lang['mail_err_derive_getmailer'] = 'Attempt to call abstract function _getMailer() in modMail class. You must implement this function in a derivative of modMail.';
$_lang['mail_err_attr_nv'] = '[[+attr]] is not a valid PHPMailer attribute and is being ignored by the implementation.';
$_lang['mail_err_unset_spec'] = 'modPHPMailer does not support unsetting specific addresses. Use reset() to clear all recipients and add back the ones you want to send to.';