title: Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at url
body: <p>It's the very famous browser error. I know it has been discussed a lot but I've noticed is a very generic error so I want to present my problem.</p>
  
  <p>I am making simple requests (get,post) on a server where I have access. My browsers (chrome, firefox) give me <code>Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at url (Reason: CORS header 'Access-Control-Allow-Origin' does not match 'null').</code> error.</p>
  
  <p>When I use some of (hacking)plugins I get the responses fine.</p>
  
  <p>What I've tried is to add on my back-end (on server):</p>
  
  <pre><code>header('Access-Control-Allow-Origin: *');
  </code></pre>
  
  <p>in <code>index.php</code> file with no luck. Any other ideas ?</p>