title: php mail() "Could not find domain on our servers"
body: <p>I'm working on a windows based server and I am wondering why a server would return this error message when using the mail() function:</p>
  
  <pre><code>Warning: mail() [function.mail]: SMTP server response: 554 Invalid From address:
  xxxxx@MyDomain.com. Could not find domain MyDomain.com on our servers.
  The email From address must be of type any_valid_name@yourdomain.com in 
  \\web-123win\winpackage22\MyDomain\web\content\mail.php on line 16
  </code></pre>
  
  <p>I mean, isn't the mail() function supposed to send emails to whatever domain we want?</p>
  
  <p>Can you help me in the understanding of this message? thanks</p>