SMTP alerts - help!

[Xhi]

Hi all,

I'mm learning HTML, Javascript & will hopefully progress to learning PHP soon.

I have a social network developed on PHP.

Members used to receive automated alerts in their inbox (e.g. yahoo) when activities happen on the site e.g. when someone comments on their photo or video. Recently, this has stopped happening. I've spoken to my hosting company, as I thought it was something on the server settings because we did not change the code.

My hosting company said the following:
"You have to use localhost or 127.0.0.1 to connect to the smtp server to send emails, not mail.domainname.com for the address, plus you also have to use smtp authentication for it."

I have checked our code, and it looks like this:
<?
require_once "../maillib/Swift.php";

require_once "../maillib/Swift/Connection/SMTP.php";

$smtp =& new Swift_Connection_SMTP("localhost", 26);
// $smtp =& new Swift_Connection_SMTP("mail.domainname.com", 26);

$smtp->setUsername("cron@domainname.com");

$smtp->setpassword("cron");

?>

This seems OK, but the alerts are still not working!

Does any one have any ideas on how we can fix this?

[is_numeric]

check your password

is it cron?