邮件程序错误:无法在joomla中实例化邮件函数

我在joomla -adminpanel- global configuration-server

Mailer  :Sendmail
Mail from   :user
From Name   :sales@user.com
Sendmail Path   :/usr/sbin/sendmail
SMTP Authentication  :No   
SMTP Security   :none
SMTP Port   :25
SMTP Username:
SMTP Password   :
SMTP Host   :localhost

我在网站中使用了form

   <form action="email.php" method="post" name="emailForm" id="emailForm" class="form-  validate">

<?php
 require_once("class.phpmailer.php");
 $mail = new PHPMailer();$mail->CharSet = 'UTF-8';
 $email = $_REQUEST['email'] ;
 $name = $_REQUEST['name'] ;
 $message = $_REQUEST['text'] ;
                 // Enable encryption, 'ssl' also accepted
  $mail->From = 'sales@example.com ';
  $mail->FromName = 'Techzo';
  $mail->addAddress('ccccc@example.in');               // Name is optional
  $mail->WordWrap = 50;                                 // Set word wrap to 50     characters
  $mail->isHTML(true);                                  // Set email format to HTML
  $mail->Subject = 'Enquiry /Contact form';
  $mail->Body    = 'Name: $name'nEmail: $email'n'n$message';

if(!$mail->send()) {
echo 'Message could not be sent.';
echo 'Mailer Error: ' . $mail->ErrorInfo;
} else {
echo 'Message has been sent';
 }
?>

我已经搜索和相应的工作，但没有在使用。作为这些编码的新手，请帮助我理解这个问题