Ayuda PHPMailer

[DavidBL]

Tengo el codigo siguiente :

<?php
require_once('includes/class.phpmailer.php');

$mail = new PHPMailer(); // defaults to using php "mail()"


$mail->AddReplyTo("[email protected]","First Last");

$mail->SetFrom('[email protected]', 'First Last');

$mail->AddReplyTo("[email protected]","First Last");

$address = "[email protected]";
$mail->AddAddress($address, "John Doe");

$mail->Subject = "PHPMailer Test Subject via mail(), basic";

$mail->AltBody = "To view the message, please use an HTML compatible email viewer!"; // optional, comment out and test

$mail->MsgHTML($body);
if(!$mail->Send()) {
echo "Mailer Error: " . $mail->ErrorInfo;
} else {
echo "Message sent!";
}


?>

Que es lo que falla??