使用PHP、PEAR发送电子邮件时出错

我在服务器上安装了Pear，然后安装了Mail和SMTP组件。然后，我将php.ini文件更新为"include_path=".C:''wamp''bin''php''php5.4.3''pear"，因为这就是Mail.php所在的位置。出于某种原因，当我通过web浏览器运行此测试脚本时，我会出现以下错误。

Warning: require_once(Mail.php): failed to open stream: No such file or directory in C:'wamp'www'email.php on line 3

和：

Fatal error: require_once(): Failed opening required 'Mail.php' (include_path='.;C:'php'pear') in C:'wamp'www'email.php on line 3

我是PHP的新手，在上周之前，我甚至从未听说过pear，因为我通常会设置交换服务器。如有任何帮助，我们将不胜感激。下面是测试脚本。

<?php
 require_once "Mail.php";
 $from = "Ty Jacobs <FROM_EMAIL>";
 $to = "Ty Jacobs <TO_EMAIL>";
 $subject = "Hi!";
 $body = "Hi,'n'nHow are you?";
 $host = "ssl://smtp.bizmail.yahoo.com";
 $port = "465";
 $username = "MYUSERNAME";
 $password = "MYPASSWORD";
 $headers = array ('From' => $from,
   'To' => $to,
   'Subject' => $subject);
 $smtp = Mail::factory('smtp',
   array ('host' => $host,
     'port' => $port,
     'auth' => true,
     'username' => $username,
     'password' => $password));
 $mail = $smtp->send($to, $headers, $body);
 if (PEAR::isError($mail)) {
   echo("<p>" . $mail->getMessage() . "</p>");
  } else {
   echo("<p>Message successfully sent!</p>");
  }
 ?>

PHP.INI文件：

; UNIX: "/path1:/path2"
;include_path = ".:/php/includes"
;
; Windows: "'path1;'path2"
;include_path = ".;c:'php'includes"
include_path=".;C:'wamp'bin'php'php5.4.3'pear"