title: ExtJs - File Uploading Error on IE8 + IE9
body: <p>I created a File Upload on the actuall EXTJS version to my Server. If the file is uploaded successfully a json response is created by the backend to process on the frontend. On Chrome and Firefox its working fine, but on IE its allways downloading the json response as file and interrupting so the process, any idea how to prevent this on IE?</p>
  
  <p>Thanks</p>