php Send mail problem (SMTP problem)

Php

Require_once ('./class.phpmailer.php ');
$mail = new Phpmailer ();
$body = "Send mail Success";
Send mail with SMTP
$mail->issmtp ();
Mail server
$mail->host = "smtp.163.com";
$mail->smtpdebug = 0;
Using SMPT Authentication
$mail->smtpauth = true;
User name for SMTP authentication
$mail->username = "";
The secret of SMTP authentication
$mail->password = "";
Set the encoding format
$mail->charset = "Utf-8";
Set theme
$mail->subject = "Test";

Set Sender
$mail->setfrom (' ****@163.com ', ' test ');

Recipient message Name
$mail->addaddress ("***@163.com", "test");//Send mail
if (! $mail->send ()) {
echo "Mailer Error:". $mail->errorinfo;
} else {
echo "Message sent!";
}
？ >
What is the problem with this code????

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