title: issue with Telerik_Web_UI_WebResource_axd
body: <p>When I run my website, I get the following error message</p>
  
  <p><strong>Cannot add duplicate collection entry of type 'add' with unique key attribute 'name' set to 'Telerik_Web_UI_WebResource_axd'</strong></p>
  
  <p>Here are the contents of web.config...</p>
  
  <pre><code>    &lt;httpHandlers&gt;
        &lt;add path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource" verb="*" validate="false"/&gt;
      &lt;/httpHandlers&gt;
  
  
    &lt;system.webServer&gt;
      &lt;modules runAllManagedModulesForAllRequests="true"/&gt;
      &lt;validation validateIntegratedModeConfiguration="false"/&gt;
      &lt;handlers&gt;
        &lt;add name="Telerik_Web_UI_WebResource_axd" verb="*" preCondition="integratedMode" path="Telerik.Web.UI.WebResource.axd" type="Telerik.Web.UI.WebResource"/&gt;
      &lt;/handlers&gt;
    &lt;/system.webServer&gt;
  </code></pre>
  
  <p>If I comment out the handlers entry.. I get the following error message...</p>
  
  <p><strong>'~/Telerik.Web.UI.WebResource.axd' is missing in web.config. RadScriptManager requires a HttpHandler registration in web.config. Please, use the control Smart Tag to add the handler automatically, or see the help for more information: Controls > RadScriptManager</strong> </p>
  
  <p>I am total at loss on how to fix this. I do not know how to use Smart Tag. I have googled, looked into SO, looked into Telerik site and can not find solution any where. I do not know if the problem is in my web.config, Virtual directory or where??? My colleagues have the same code base and web.config and it works for them.</p>
  
  <p><strong>EDIT</strong>
  Here is my development machine setup...</p>
  
  <p>Windows 7 Enterprise Service Pack 1 64 bit OS</p>
  
  <p>Visual Studio 2010 Enterprise Service pack 1 IIS version 7.5</p>
  
  <p>Please help.</p>