Please include <scriptmanager> in your child page.
<asp:content id="cphCl" contentplaceholderid="cphMain" runat="server" xmlns:asp="#unknown">
<asp:scriptmanager id="ScriptManager1" runat="server"></scriptmanager>
<asp:UpdatePanel runat="server" ID="upGrid" UpdateMode="Conditional" RenderMode="Block" >
If the RenderMode property is set to Inline
, the content of an UpdatePanel control is rendered inside an HTML <span> element. If the RenderMode property is set to Block
, it is rendered inside an HTML <div> element.
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