title: asyncfileupload inside update panel not triggering the upload method
body: <p>I am having a <code>asyncfileupload</code> inside a update panel, I want to upload the file once when a file is selected , the same code works well outside the update panel but my design is in such a way that I can put this outside the update panel, how can I make this work</p>
  
  <pre><code>  &lt;asp:UpdatePanel ID="UP_DDL" runat="server" UpdateMode="Always" Visible="true"
                      RenderMode="Inline"&gt;
        &lt;ContentTemplate&gt;  
     &lt;asp:asyncfileupload id="AFU_Doc" runat="server"
       uploadingbackcolor="Yellow" onuploadedcomplete="btnDocUpload_Click"
        onclientuploadcomplete="sa" throbberid="spanUploading2" /&gt;
         &lt;span id="spanUploading2" runat="server"&gt;Uploading...&lt;/span&gt;
        &lt;/ContentTemplate&gt;
           &lt;Triggers&gt;
              &lt;asp:AsyncPostBackTrigger ControlID="AFU_Doc" /&gt;
           &lt;/Triggers&gt;
    &lt;/asp:UpdatePanel&gt;
  </code></pre>