Q:

Newb PHP mail form not working

I'm sure this is a very basic answer and that I'm overlooking something obvious.
I'm trying to get a mail form to work correctly, but it keeps giving sending me to the the php page with the error message stating that the name and comments I entered do not appear to be valid.
My HTML:
<div id="footer" class="container">
 <header>
<h2>Questions or comments? <strong>Get in touch:</strong></h2>
 </header>
     <div class="row">
    <div class="6u">
       <section>
         <div id="contact-form">
        <form name="feedback" method="post" action="php/send_form_email.php">
          <div class="row half">    
                     <div class="6u">
                   <input name="name" placeholder="Name" type="text" class="text" />    
             </div>
         <div class="6u">
        <input name="email" placeholder="Email" type="text" class="text" />
             </div>
      </div>
    <div class="row half">
         <div class="12u">
        <textarea name="message" placeholder="Message"></textarea>
         </div>
    </div>
    <div class="row half">
       <div class="12u">
        <input type="submit" value="submit">
                       <a href="php/send_form_email.php"></a>
       </div>
    </div>
     </form>
  </div>
   </section>

My PHP:
    <?php

    if(isset($_POST['email'])) {

    $email_to = "sforcash@gmail.com";

    $email_subject = "Message from rmcabinetry.com";

    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 />";

        die();

    }

    // validation expected data exists

    if(!isset($_POST['name']) ||

        !isset($_POST['email']) ||

        !isset($_POST['message'])) {

        died('We are sorry, but there appears to be a problem with the form you submitted.');       

    }

    $first_name = $_POST['name']; // required

    $email_from = $_POST['email']; // required

    $comments = $_POST['message']; // 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($string_exp,$name)) {

    $error_message .= 'The Name you entered does not appear to be valid.<br />';

  }

  if(strlen($message) < 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);

    }

    $email_message .= "Name: ".clean_string($name)."\n";

    $email_message .= "Email: ".clean_string($email_from)."\n";

    $email_message .= "Message: ".clean_string($message)."\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 -->

Thank you for contacting Riley Mills. We will be in touch with you very soon.

<?php

}

?>

A:

This is the error:
if(strlen($message) < 2) {
You defined the variable as $comments earlier but reference $message here. There is no $message defined any place in your code.
Solution:
Replace $message with $comments in that section, as well as where it appears further below:
$email_message .= "Message: ".clean_string($message)."\n";
OR
Replace $comments with $message above where it's defined:
$comments = $_POST['message']; // required

