Defines the method for sending mail.<br><br><strong>PHP</strong> is the default, and uses built-in PHP wrappers for processing.<br><strong>smtpauth</strong> should be used by most sites, as it provides secure sending of authenticated email. You must also configure your smtpauth settings in the appropriate fields in this admin section.<br><strong>Gmail</strong> is used for sending emails using the Google mail service, and requires the [less secure] setting enabled in your gmail account.<br><strong>sendmail</strong> is for linux/unix hosts using the sendmail program on the server<br><strong>sendmail-f</strong> is only for servers which require the use of the -f parameter to use sendmail. This is a security setting often used to prevent spoofing. Will cause errors if your host mailserver is not configured to use it.<br><strong>Qmail</strong> is used for linux/unix hosts running Qmail as sendmail wrapper at /var/qmail/bin/sendmail.<br><br>MOST SITES WILL USE [smtpauth].