 <p>Check this question: <a href="http://stackoverflow.com/questions/16052758/kendoui-uploader-remove">KendoUI Uploader Remove</a></p> <p>For me, changing the return type did it.</p> <p>From</p> <pre><code>public ActionResult RemoveFile(string[] fileNames) { return Content(""); } </code></pre> <p>To</p> <pre><code>public ActionResult RemoveFile(string[] fileNames) { return Json(""); } </code></pre> <p>I left my SaveFile() function with <code>return Content("");</code></p>