I installed GNU Social over XAMPP on Windows.
But in the last page of the installation it show me the next Warning:
Warning: 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() in C:\xampp\php\PEAR\Mail\mail.php on line 153
Why you dont use PHPMailer to send emails?
or simply send emails without the SMTP Configuration.
Greetings To You!