I think the specs are in RFC 822. You should find if there. Satyam "AndreaD" <andrea.davidson@xxxxxxxxxxxx> wrote in message news:20050416172803.43376.qmail@xxxxxxxxxxxxxxxx > When trying to send mail via localhost I get the following error > > Warning: mail() [function.mail]: SMTP server response: 550 5.7.1 > > > Any ideas?/ > > > RH -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php