First things first... I know mail deliverability is effected by hundreds of factors and so it's never possible to say for SURE if one specific thing is the cause. (I do *not* expect this.)

My question is whether is normal/expected for mail servers to block messages which have a different `From:` header. My contact form handler uses this so that the reciptient can reply to the sender (code below). Gmail accounts are able to receive the messages. But my client has an institutional `.edu` email address and the emails aren't getting delivered.

Here's a minimal version of my code:

```
<?php 

$first_name = 'John';
$last_name = 'Smithy';
$email = "myemail@whyisntthisworking.com";
$msg = "This is a test email. If you received it things are working.";

$test_email = (isset($_POST['test_email'])) ? $_POST['test_email'] : FALSE;

$to;
$from = $email;
$subject = "Contact from JamesGregoryMD.com";
$body = wordwrap( "{$first_name} {$last_name}:\n\n{$msg}\n\n{$email}\n{$phone}", 70);
$headers = "From: {$from}" . "\r\n";

if ($test_email) {
    # send email
    $return = mail($test_email,"Test email",$body, $headers);

    if ($return) {
        echo "<h1>MAIL SENT</h1>";
    } else {
        echo "<h1>MAIL NOT SENT</h1>";
    }
}
?>

<form id="contact" method="post">
    <input type="email" name="test_email" placeholder="email" />
    <input type="submit" value="Send" />
</form>

```