TreeView to pdf

Hi All,

I have created a web form that will display the Organisation Chart in Tree form. I have dynamically created Tree View control from code behind.Everything working fine.The problem is when I am exporting TreeView to pdf I am getting te following error

"0x800a139e - JavaScript runtime error: Sys.WebForms.PageRequestManagerParserErrorException: The message received from the server could not be parsed."

The source code is

UpdateProgress1.Visible =

false;

            ImgTopBanner.Visible =

false;

            Response.AddHeader(

"content-disposition","attachment;filename=TestPage.pdf");

            Response.Cache.SetCacheability(

HttpCacheability.NoCache);

StringWriter sw = newStringWriter();

HtmlTextWriter hw = newHtmlTextWriter(sw);

this.Page.RenderControl(hw);

//TrvPrint.RenderControl(hw);

StringReader sr = newStringReader(sw.ToString());

Document pdfDoc = newDocument(PageSize.A4, 10f, 10f, 100f, 0f);

HTMLWorker htmlparser = newHTMLWorker(pdfDoc);

PdfWriter.GetInstance(pdfDoc, Response.OutputStream);

            pdfDoc.Open();

            htmlparser.Parse(sr);

            pdfDoc.Close();

            Response.Write(pdfDoc);

            Response.End();

Please help