title: Cross Domain upload fails after about 1 minute
body: <p>We have a cross-domain process to upload files using javascript's XMLHttpRequest (which enables a progress events to display a progress bar to users),
  this process works fine after setting the needed configurations in web.config:</p>
  
  <pre><code>&lt;httpProtocol allowKeepAlive="true"&gt;
    &lt;customHeaders&gt;
      &lt;add name="Access-Control-Allow-Origin" value="*"/&gt;
    &lt;/customHeaders&gt;
  &lt;/httpProtocol&gt;
  </code></pre>
  
  <p>The problem is when trying to upload large files (more than 100 MB), so the request will take a long time (more than 1 minute), the XMLHttpRequest catch a failure event, and the response is as follows (as google chrome display it in the console):</p>
  
  <pre><code>XMLHttpRequest cannot load http://oursite.net/Controller/UploadFile. Origin http://secondsite.net is not allowed by Access-Control-Allow-Origin.
  </code></pre>
  
  <p>But after testing the server side, the file was uploaded and saved, so the Action was completely performed on the server !!</p>
  
  <p>We think that this problem is caused by something such as a timeout (because this problem doesn't occur when the request is not passing a 1 minute).</p>
  
  <p>Note: the server side is an Asp.net MVC project.
  Any idea?</p>