title: Setting the Access-Control-Allow-Origin CORS for wordpress site
body: <p>I had some problems to set a correct cors header for using external resource in my wordpress installation. I have a subdomain which exposed by another domian name.</p>
  
  <p>I've got following error by using some plugin which load resources from my website by using an ajax call:</p>
  
  <pre><code>XMLHttpRequest cannot load [resource-URL] No 'Access-Control-Allow-Origin' header
  </code></pre>