where is issue with SMTP authentication ?

Hello, I am very new to PHP, i creating a website and got hosting here on Winhost. i have send email form which normally works but at this hosting it is not working. I understand SMTP is not working on this host and i saw that link too https://support.Winhost.com/kb/a826/how-to-send-email-from-a-php-application.aspx but i am not understanding what changes i should in my code for it to work.

Please see the below code and help me in getting the required change it.

FILE 1, register.php (this is form)
<form name="contactform" method="post" action="send_form_email.php">
<table width="360">
<tr class="style4">
<td width="166" valign="top" class="style4">
<label for="first_name">First Name *</label> </td>
<td width="182" valign="top">
<input type="text" name="first_name" maxlength="50" size="30">
</td>
</tr>
<tr class="style4">
<td valign="top" class="style4"">
<label for="last_name">Last Name *</label> </td>
<td valign="top">
<input type="text" name="last_name" maxlength="50" size="30">
</td>
</tr>
<tr class="style4">
<td valign="top" class="style4">
<label for="email">Email Address *</label> </td>
<td valign="top">
<input type="text" name="email" maxlength="80" size="30">
</td>
</tr>
<tr class="style4">
<td valign="top" class="style4">
<label for="telephone">Telephone Number</label> </td>
<td valign="top">
<input type="text" name="telephone" maxlength="30" size="30">
</td>
</tr>
<tr class="style4">
<td valign="top" class="style4">Address</td>
<td valign="top"><textarea name="address" cols="23" rows="6" id="address"></textarea></td>
</tr>
<tr class="style4">
<td valign="top" class="style4">Gender</td>
<td valign="top"><select name="gender" id="gender">
<option value="male">Male</option>
<option value="female">Female</option>
</select></td>
</tr>
<tr class="style4">
<td valign="top" class="style4">Date of Birth </td>
<td valign="top"><p>
<input name="dob" type="text" id="dob" size="30" maxlength="30">
<br>
e.g. 22/2/1998</p></td>
</tr>
<tr class="style4">
<td valign="top" class="style4">Course</td>
<td valign="top"><select name="course" id="course">
<option value="Mental Calculator">Mental Calculator</option>
<option value="Human Callender">Human Callender</option>
<option value="Photographic Memory">Photographic Memory</option>
</select></td>
</tr>
<tr class="style4">
<td valign="top" class="style4">
<label for="comments">Comments </label></td>
<td valign="top">
<textarea name="comments" cols="23" rows="6"></textarea>
</td>
</tr>
<tr>
<td colspan="2" style="text-align:center">
<div align="right">
<input name="submit" type="submit" value="Submit">
</div></td>
</tr>
</table>
</form></td>
</tr>
</table>

FILE 2, send_form_email.php

<?php
if(isset($_POST['email'])) {

// EDIT THE 2 LINES BELOW AS REQUIRED
$email_to = "[email protected]";
$email_subject = "Email for MAPD";


function died($error) {
// your error code can go here
echo "We are very sorry, but there were error(s) found with the form you submitted. ";
echo "These errors appear below.<br /><br />";
echo $error."<br /><br />";
echo "Please go back and fix these errors.<br /><br />";

}

// validation expected data exists
if(!isset($_POST['first_name']) ||
!isset($_POST['last_name']) ||
!isset($_POST['email']) ||
!isset($_POST['telephone']) ||
!isset($_POST['address']) ||
!isset($_POST['gender']) ||
!isset($_POST['dob']) ||
!isset($_POST['course']) ||
!isset($_POST['comments'])) {
died('We are sorry, but there appears to be a problem with the form you submitted.');
}

$first_name = $_POST['first_name']; // required
$last_name = $_POST['last_name']; // required
$email_from = $_POST['email']; // required
$telephone = $_POST['telephone']; // not required
$address = $_POST['address']; // not required
$gender = $_POST['gender']; // not required
$dob = $_POST['dob']; // not required
$course = $_POST['course']; // not required
$comments = $_POST['comments']; // required

$error_message = "";
$email_exp = '/^[A-Za-z0-9._%-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,4}$/';
if(!preg_match($email_exp,$email_from)) {
$error_message .= 'The Email Address you entered does not appear to be valid.<br />';
}
$string_exp = "/^[A-Za-z .'-]+$/";
if(!preg_match($string_exp,$first_name)) {
$error_message .= 'The First Name you entered does not appear to be valid.<br />';
}
if(!preg_match($string_exp,$last_name)) {
$error_message .= 'The Last Name you entered does not appear to be valid.<br />';
}
// if(strlen($comments) < 2) {
// $error_message .= 'The Comments you entered do not appear to be valid.<br />';
// }
if(strlen($error_message) > 0) {
died($error_message);
}
$email_message = "Form details below.\n\n";

function clean_string($string) {
$bad = array("content-type","bcc:","to:","cc:","href");
return str_replace($bad,"",$string);
}

$email_message .= "First Name: ".clean_string($first_name)."\n";
$email_message .= "Last Name: ".clean_string($last_name)."\n";
$email_message .= "Email: ".clean_string($email_from)."\n";
$email_message .= "Telephone: ".clean_string($telephone)."\n";
$email_message .= "Address: ".clean_string($address)."\n";
$email_message .= "Gender: ".clean_string($gender)."\n";
$email_message .= "Date of Birth: ".clean_string($dob)."\n";
$email_message .= "Course: ".clean_string($course)."\n";
$email_message .= "Comments: ".clean_string($comments)."\n";


// create email headers
$headers = 'From: '.$email_from."\r\n".
'Reply-To: '.$email_from."\r\n" .
'X-Mailer: PHP/' . phpversion();
@mail($email_to, $email_subject, $email_message, $headers);
?>
<!-- include your own success html here -->
<p><span class="style1">Thank you so much for your comments</span></p>
<p class="style17 style1 style5">Best Regards,</p>
<p><span class="style17 style1 style5">MAPD</span>
<?php
}
?>

 

please check below code and tell where is the mistake? i don't receive a test email.
should i upload Mail.php file in my hosting folder? if yes from where i can get it? or is there any other error?

<?php
require_once "Mail.php";
$from = "Sender <[email protected]>";
$to = "Recipient <[email protected]>";
$subject = "This is a test email sent via php";
$body = "This is a test email";
$host = "mail.mapd.co";
$username = "[email protected]";
$password = "xxxxxxxx";
$headers = array ('From' => $from,
'To' => $to,
'Subject' => $subject);
$smtp = Mail::factory('smtp',
array ('host' => $host,
'auth' => true,
'username' => $username,
'password' => $password));
$mail = $smtp->send($to, $headers, $body);
?>