无法使用imap_open连接到peoplepc.com邮件服务器

Question

我只是无法通过imap连接到peoplepc.com webmail， 这是代码：

    $host  = "{imap.peoplepc.com:143/imap}";
    $user  = "User@peoplepc.com";
    $pass  = "Password";
    try {
        $mbox = imap_open($host, $user, $pass) or die("can't connect: " . imap_last_error());
        if ( $mbox==true) {

           //do this

        } else {
           //do this instead

        }
    }
    catch (Exception $e) {
       //handle exception 

    }

请你告诉我我做错了什么