Quick Email config File

[eluser]FreshProgrammer[/eluser]
Hi..

I follow and set the setting as showed above.But,still i can not send email through this codeigniter.

Below shows the error message that i had encountered.

Severity: Warning

Message: mail() [function.mail]: Failed to connect to mailserver at "localhost" port 25, verify your "SMTP" and "smtp_port" setting in php.ini or use ini_set()

Filename: libraries/Email.php

Line Number: 1519

If i am not mistaken,the space for smtp just leave it blank right?
Does anyone know how to send the email correctly?

Thank You