Can anyone explain why this code successfully sends to some email addresses, but not to others (not even to spam folder) and yet I can successfully send emails directly to the same addresses.
$headers = 'From: ' . $email_from . "\r\n".'Reply-To: ' . $email_from."\r\n" . 'X-Mailer: PHP/' . phpversion();
@mail($_SESSION['email_to'], $email_subject, $email_message, $headers);
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