AjaxFileUpload not known element in asp.net

Question

I have tried to use ajax file upload bu the tag is not found even it is in the toolbox 

 I added this to config file

<httpHandlers>

<add verb="*" path="AjaxFileUploadHandler.axd" type="AjaxControlToolkit.AjaxFileUploadHandler, AjaxControlToolkit "/>

<controls>

<add namespace="AjaxControlToolkit" assembly="AjaxControlToolkit" tagPrefix="ajaxToolkit"/>

and this to aspx file 

<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %>

<asp:ToolkitScriptManager runat="server"></asp:ToolkitScriptManager>

 But still not working Please help