HTML PHP电子邮件代码不起作用

Question

请允许任何人看到这个PHP代码中的任何错误，我已经尝试了所有我能想到的没有运气，我试图获得一个表单将数据发送到PHP然后发送电子邮件但每次我尝试在服务器上，我得到的是“消息失败。”＃39;

 <?php
    $field_name = $_POST['cf_name'];
    $field_email = $_POST['cf_email'];
    $field_message = $_POST['cf_message'];

    $mail_to = 'MyEmail@hotmail.co.uk';
    $subject = 'Message from a site visitor '.$field_name;

    $body_message = 'From: '.$field_name."\n";
    $body_message .= 'E-mail: '.$field_email."\n";
    $body_message .= 'Message: '.$field_message;

    $headers = 'From: '.$field_email."\r\n";
    $headers .= 'Reply-To: '.$field_email."\r\n";

    $mail_status = mail($mail_to, $subject, $body_message, $headers);

    if ($mail_status) { ?>
        <script language="javascript" type="text/javascript">
            alert('Thank you for the message. We will contact you shortly.');
            window.location = 'default.html';
        </script>
    <?php
    }
    else { ?>
        <script language="javascript" type="text/javascript">
            alert('Message failed.');
            window.location = 'default.html';
        </script>
    <?php
    }
    ?>