title: The type or namespace name 'Entity' does not exist in the namespace 'System.Data'
body: <p>I'm using WS class and it gave me error when I run the application:</p>
  
  <pre><code>The type or namespace name 'Entity' does not exist in the namespace 'System.Data' 
  </code></pre>
  
  <p>I have a reference to the <code>System.Data;</code> and to <code>System.Data.Entity;</code>
  But no changes. I keep getting the error. I have also in the web.config the line: </p>
  
  <pre><code>&lt;compilation debug ="true" targetFramework="4.0"/&gt;
  </code></pre>