Error: Sys.InvalidOperationException: Two components with the same id 'RadProgressBar1' can't be added to the application.

Workaround: Use RadScriptManager

		<asp:ScriptManager ID="Scriptmanager1" runat="server" /> <-- issue
		<%--<telerik:RadScriptManager runat="server" ID="rsm1"></telerik:RadScriptManager>--%> <-- workaround
		<asp:UpdatePanel ID="Updatepanel1" runat="server">
			<ContentTemplate>
					<asp:Button ID="Button1" Text="AJAX" runat="server" />
	
					<telerik:RadProgressBar runat="server" ID="RadProgressBar1" />
			</ContentTemplate>
		</asp:UpdatePanel>