title: 'AjaxControlToolkit' is undefined Error
body: <p>I am using the <strong>AjaxControlToolkit</strong> in VS2005, and it works fine. I do have some issues though, when I go to some pages I have, then click back, I get this JavaScript error:</p>
  
  <blockquote>
    <p>'AjaxControlToolkit' is undefined</p>
  </blockquote>
  
  <p>I have searched MSDN forums, and google, and tried many of the solutions, but none have worked. I have tried, <code>EnablePartialRendering="true",</code> and others. Short of rewriting everything and changing the workflow of my application, is there any way to find the root cause of this, or fix it?
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