title: Could not load type 'System.Web.Script.AjaxFrameworkAssemblyAttribute' from assembly 'System.Web.Extensions,
body: <p>I recently switched to VS 2010. While using <code>AjaxToolkit version=4.1.51116.0</code>, I am getting run-time error :</p>
  
  <blockquote>
    <p>Could not load type 'System.Web.Script.AjaxFrameworkAssemblyAttribute'
    from assembly 'System.Web.Extensions, Version=4.0.0.0,
    Culture=neutral, PublicKeyToken=31bf3856ad364e35'.<em>*</em>*</p>
  </blockquote>
  
  <p>This error is coming while using any of the AJAX toolkit control.
  I am using ToolkitScriptManager.</p>
  
  <p>How to solve this error?
  suggestions are greatly appreciated.</p>