Hi, we are using RadAjaxManager in Master page and RadAjaxManagerProxy in Content Page where loading panel is not working. Below is the sample code for the same condition:

Master Page:
<telerik:RadAjaxManager ID="RadAjaxManager1" EnableAJAX="true" runat="server"></telerik:RadAjaxManager>
<asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">            
</asp:ContentPlaceHolder>

Content Page:
    <telerik:RadCodeBlock ID="RCB1" runat="server">
        <script type="text/javascript">
            function Submit() {.....}
        </script>
    </telerik:RadCodeBlock>

<telerik:RadAjaxManagerProxy ID="RadAjaxManagerProxy1" runat="server">
        <AjaxSettings>        
            <telerik:AjaxSetting AjaxControlID="ajaxPanel1">
                <UpdatedControls>
                    <telerik:AjaxUpdatedControl ControlID="ajaxPanel1" LoadingPanelID="RadAjaxLoadingPanel1" />
                </UpdatedControls>
            </telerik:AjaxSetting>
        </AjaxSettings>
    </telerik:RadAjaxManagerProxy>

    <telerik:RadScriptManager ID="RadScriptManager1" runat="server">
    </telerik:RadScriptManager>

<telerik:RadAjaxLoadingPanel ID="RadAjaxLoadingPanel1" BackgroundPosition="Center" runat="server" Transparency="30" BackColor="#E0E0E0">
        <div>
            <asp:Image ID="Image1" runat="server" ImageUrl="~/Images/ajax-loader.gif" AlternateText="loading"></asp:Image>
        </div>
    </telerik:RadAjaxLoadingPanel>

Earlier we were not using RadAjaxManagerProxy and RadAjaxManager was implemented in Content Page only. After upgrading application to .Net framework 4.5 and telerik version to 2016.2.607.45, we included proxy and then this issue started occurring. Kindly help in the scenario how can we use loading panel through manager proxy?

Hello Avnish,

The presented code looks absolutely correct to me. can you please try to remove the LoadingPanel image and set a Skin for it so that the image comes form the Skin and see ho it goes in this case.

Regards,
Maria Ilieva
Telerik by Progress