Contact from not send complete message

[nwelte]

I am building my first website for my business. I put in a contact me form. I receive e-mails that do not include the requested data. Here is the html code:

<div id="contact_container">
          <h1>CONTACT ME</h1>
          <p class="contact_text">FREE CONSULTATION</p>
          <form action="mail.php" method="post"> <input size="33" name="name" required=""

          placeholder="First and Last Name"> <input name="email" required=""

          size="33" placeholder="E-mail Address" type="text"> <input name="phonenumber"

          required="" size="33" placeholder="Phone Number" type="text"><textarea

          name="message" rows="6" cols="25" placeholder="Message"></textarea>
        <input value="Send" type="submit"> </form>
      <div id="address">

Here is the PHP:

<?php
$name = $_Post['name'];
$email = $_Post['email'];
$phonenumber = $_Post['phoneumber'];
$message = $_Post['message'];
$formcontent="From: $name \n Message: $message \n Phone Number: $phonenumber";
$recipient = "[e-mail]";
$subject = "Contact Form";
$mailheader = "From: $email \r\n";
mail ($recipient, $subject, $formcontent, $mailheader) or die("Error!);
echo "Thank You!";
?>

Where have I gone wrong?

[bradgrafelman]

$Post is an undefined variable. Perhaps you meant $POST instead?

Also, you never check to see if any data was actually POST'ed before sending the e-mail. Of course, your PHP code snippet also includes a parse error, but that would suggest that you wouldn't get any e-mails at all, so I'm assuming that was just some sort of copy-paste error when creating your post.

[sneakyimp]

That script is a piece of junk and will, in all likelihood, be abused by spammers using email injection.

EDIT: I apologize for my rather rude comment. You need to make sure that the email address submitted are actually email addresses and don't contain any newline chars, etc. You should probably use PEAR::Mail or PHPMailer or some other such program rather than relying on the raw mail function.