title: System.webserver has invalid child element "cors"
body: <p>This is a completed project from my team, but i dun know why i getting this .
  <a href="https://i.stack.imgur.com/psQaU.png" rel="noreferrer"><img src="https://i.stack.imgur.com/psQaU.png" alt="cors in web.config" /></a></p>
  <p>In my config.cs. This already enable cors . cors already installed in Nuget package:</p>
  <pre><code>public static void Register(HttpConfiguration config)
      {
          // Web API configuration and services
          
          SystemDiagnosticsTraceWriter traceWriter = config.EnableSystemDiagnosticsTracing();
          traceWriter.IsVerbose = true;
          traceWriter.MinimumLevel = TraceLevel.Debug;
  
          // Enable Web API routes by attribute
          config.MapHttpAttributeRoutes();
  
          EnableCorsAttribute cors = new EnableCorsAttribute(&quot;*&quot;,&quot;*&quot;,&quot;*&quot;);
          config.EnableCors(cors);
      }
  </code></pre>