Captcha

[defiantdezign]

hey there, having some issues with this captcha image that im dropping on a form. Not getting any errors its just not checking the captcha field when submitted. Below is a snippet. Any in sight into this would be great, im pretty new to PHP so anything helps.

Thanks

<?php
session_start();
if( isset($_POST['submit'])) {
if(($_SESSION['security_code'] == $_POST['security_code']) && (!empty($_SESSION['security_code'])) ) {
echo 'Thank you.'.$_POST['message'].'"';
unset($_SESSION['security_code']);
} else {
echo 'Sorry, you have provided an invalid security code'.$_POST['message'].'""';
}
} else {}
?>

[infrenion]

Is the captcha image displayed properly?