Hi,
You lack a
ScriptManager script...
Try to insert this in client page:
<asp:scriptmanager id="ScriptManager1" runat="server" enablepagemethods="true" xmlns:asp="#unknown" />
As shown below...
<body>
<form id="form1" runat="server">
<asp:scriptmanager id="ScriptManager1" runat="server" enablepagemethods="true" xmlns:asp="#unknown" />
<%--...Some code here.... --%>
</form>
</body>
Hope this could help...
Do not forget to vote if could help...
Regards,
Al