Problem:

RadEditor Content not saved on page postback.

Solution:

Add UseSubmitBehavior="false" to the button that’s causing page postback.

<asp:Button ID="Button1" runat="server" 
OnClick="Button1_Click" Text="Button1"  UseSubmitBehavior="false"  />

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                There’s a harsh reality web application developers need to face up to; we don’t do security very well. A report from WhiteHat Security last year reported “83% of websites have had a high, critical or urgent issue”. That is, quite simply, a staggeringly high number and it’s only once you start to delve into to depths of web security that you begin to understand just how easy it is to inadvertently produce vulnerable code.

Error Message:

Could not find any resources appropriate for the specified culture or the neutral culture.  Make sure "AjaxControlToolkit.Properties.Resources.NET4.resources" was correctly embedded or linked into assembly "AjaxControlToolkit" at compile time, or that all the satellite assemblies required are loadable and fully signed.

Reason:

AjaxControlToolkit’s control load reference refers to the base System.Web.UI.Control method which is present as a part of the ASP.NET AJAX Libraries and those libraries are referenced only when the ScriptManager is referenced in the page.

Solution:

Add ScriptManager in the page and this error would be resolved.

            <asp:ScriptManager ID="ScriptManager1" runat="server">
            </asp:ScriptManager>

   List<string> liItems= (from ListItem item in ListBox1.Items where item.Selected select item.Value).ToList();