title: PHP Mail - Can't Receive On Certain Mail Servers
body: <p>Using the php mail() function to send out emails when a user requests a login.</p>
  
  <p>It was working fine last week, emails were being received by all my coworkers who share the same mail server for our company. Now however, the emails are not being received by that mail server, but received on others (comcast.net, uservoice.com, gmail.com, etc.) just fine.</p>
  
  <p>No error from the php mail() function so the emails are being sent, just for whatever reason they are all of a sudden blocked by our mail server.</p>
  
  <p>No settings have been changed to the php scripts or the mail server.</p>
  
  <p>Any ideas??? I have tried everything!</p>
  
  <pre><code>&lt;?PHP
      $timestamp = date('Y-m-d H:i:s');
      $to = 'james.hickman@MYCOMPANY.com';
      $from = 'support@MYCOMPANY.uservoice.com';
      $subject = 'Admin Test';
      $message = 'Just a simple test message! - '.$timestamp;
  
  
      $headers .= "Reply-To: ".$from."\r\n";
      $headers .= "Return-Path: ".$from."\r\n";
      $headers .= "From: ".$from."\r\n";
      $headers .= "Organization: MYCOMPANY Support\r\n";
      $headers .= "MIME-Version: 1.0\r\n";
      $headers .= "Content-type: text/plain; charset=iso-8859-1\r\n";
      $headers .= "X-Priority: 3\r\n";
      $headers .= "X-Mailer: PHP". phpversion() ."\r\n" ;
      if(mail($to, $subject, $message, $headers, "-f ".$from))
          echo "Success!";
      else
          echo "Failed";
  ?&gt;
  </code></pre>