HTML邮件表单无法发送邮件问题求助

我正被HTML邮件表单的问题困扰，懂编程的人可能觉得简单，但我没有编程经验。问题是这个表单无法向我的实际收件箱发送邮件，请问我是不是遗漏了什么？

相关站点部署地址为http://beta2.folldalreklame.no，站点源码可从http://www.folldalreklame.no/StackOverflowHelp.zip获取。

以下是HTML表单代码：

<div class="col-md-8">
    <h3>Send en melding</h3>
    <form id="form-contact"  method="post" class="clearfix ts-form ts-form-email" data-php-path="assets/php/email.php">
        <div class="row">
            <div class="col-md-6 col-sm-6">
                <div class="form-group">
                    <label for="form-contact-name">Navn *</label>
                    <input type="text" class="form-control" id="form-contact-name" name="name" placeholder="Navn" required>
                </div>
                <!--end form-group -->
            </div>
            <!--end col-md-6 col-sm-6 -->
            <div class="col-md-6 col-sm-6">
                <div class="form-group">
                    <label for="form-contact-email">E-post *</label>
                    <input type="email" class="form-control" id="form-contact-email" name="email" placeholder="E-post" required>
                </div>
                <!--end form-group -->
            </div>
            <!--end col-md-6 col-sm-6 -->
        </div>
        <!--end row -->
        <div class="form-group">
            <label for="form-contact-subject">Emne *</label>
            <input type="text" class="form-control" id="form-contact-subject" name="subject" placeholder="Emne" required>
        </div>
        <!--end form-group -->
        <div class="row">
            <div class="col-md-12">
                <div class="form-group">
                    <label for="form-contact-message">Melding *</label>
                    <textarea class="form-control" id="form-contact-message" rows="5" name="message" placeholder="Melding" required></textarea>
                </div>
                <!--end form-group -->
            </div>
            <!--end col-md-12 -->
        </div>
        <!--end row -->
        <div class="form-group clearfix">
            <button type="submit" class="btn btn-primary float-right ts-btn-arrow" id="form-contact-submit">Send melding</button>
        </div>
        <!--end form-group -->
        <div class="form-contact-status"></div>
    </form>
    <!--end form-contact -->
</div>
</div>
<!--end row-->
</div>
</div>
<!--end container-->
</section>
<!--end #contact-->

以下是email.php代码：

<?php
mb_internal_encoding("UTF-8");

$to = 'post@folldalreklame.no';
$subject = 'Melding via nettside';

$name = "";
$email = "";
$phone = "";
$message = "";

if( isset($_POST['name']) ){
    $name = $_POST['name'];

    $body .= "Name: ";
    $body .= $name;
    $body .= "

";
}
if( isset($_POST['subject']) ){
    $subject = $_POST['subject'];
}
if( isset($_POST['email']) ){
    $email = $_POST['email'];

    $body .= "";
    $body .= "Email: ";
    $body .= $email;
    $body .= "

";
}
if( isset($_POST['phone']) ){
    $phone = $_POST['phone'];

    $body .= "";
    $body .= "Phone: ";
    $body .= $phone;
    $body .= "

";
}
if( isset($_POST['message']) ){
    $message = $_POST['message'];

    $body .= "";
    $body .= "Message: ";
    $body .= $message;
    $body .= "

";
}

$headers = 'From: ' .$email . "
";

if (filter_var($email, FILTER_VALIDATE_EMAIL)) {
mb_send_mail($to, $subject, $body, $headers);
    echo '<div class="status-icon valid"><i class="fa fa-check"></i></div>';
}
else{
    echo '<div class="status-icon invalid"><i class="fa fa-times"></i></div>';
}

恳请各位提供帮助。

内容的提问来源于Stack Exchange，提问作者Lars-Kristian Nerbø