title: Unrecognized configuration section system.web/system.webServer
body: <p>I am following the walkthrough for <a href="http://msdn.microsoft.com/en-us/library/ms228090.aspx" rel="nofollow">creating a synchronous http handler</a> and choose the registration via integrated mode in IIS 7.5.</p>
  
  <p>Using a web site project in Visual Studio 2010, for .NET 4.0, on IIS 7.5 the error message for the following part in web.config:</p>
  
  <pre><code>&lt;configuration&gt;
      &lt;system.web&gt;
          &lt;compilation debug="false" targetFramework="4.0"&gt;
          &lt;/compilation&gt;
          &lt;system.webServer&gt;
              &lt;validation validateIntegratedModeConfiguration="false" /&gt;
              &lt;handlers&gt;
                  &lt;add verb="*" path="*.sample" name="Logger" type="Logger"/&gt;
              &lt;/handlers&gt;
          &lt;/system.webServer&gt;
          &lt;pages controlRenderingCompatibilityVersion="3.5" clientIDMode="AutoID"/&gt;
      &lt;/system.web&gt;
  &lt;/configuration&gt;
  </code></pre>
  
  <p>is: Unrecognized configuration section system.web/system.webServer. It si an invalid child element. How should I fix it and why is it not recognized?</p>