Sending Mail via PHP need help

[SonN]

Hello everyone, I'm new here.
I'm trying make a form to send to an external mail server using PHP and receive this error message: mail() [function.mail]: SMTP server response: 503 This mail server requires authentication when attempting to send to a non-local e-mail address. Please check your mail client settings or contact your administrator to verify that the domain or address is defined for this server. in C:\Inetpub\vhosts\saugusdrugs.com\httpdocs\pharmacy\form_refillrx_rx.php on line 464

Does anyone know how to trouble shoot this problem? Thank you in advance.

 

[Rickygolucky]

Try to add the IP address of the mail gateway to the [mail function] section in your php.ini file and restart your web server.

 

[NaszmulT]

Have you configure DNS reply for you site. Before sending mail please ping your DNS like..
ping www.example.com

if you got the reply then try to send email because without a DNS server you can't send email.

________________
Parallel Universe