title: ERROR Could not load file or assembly 'AjaxControlToolkit' or one of its dependencies
body: <p>I'm deploying my website on the server.</p>
  <p>My website is done using asp.net c# 4 and EF 4.</p>
  <p>I receive this error:</p>
  <blockquote>
  <p>Could not load file or assembly 'AjaxControlToolkit' or one of its dependencies. This assembly is built by a runtime newer than the currently loaded runtime and cannot be loaded.</p>
  </blockquote>
  <p>Any idea how could I fix it?</p>