title: A route named 'MS_attributerouteWebApi' is already in the route collection
body: <p>I recently added <code>Microsoft.AspNet.WebApi.WebHost</code> to a MVC WebAPI project which would allow me to use the <code>[Route("api/some-action")]</code> attribute on my action. I solved some errors using <a href="http://www.asp.net/web-api/overview/web-api-routing-and-actions/attribute-routing-in-web-api-2" rel="noreferrer">this article</a> but can't solve the third error below. Added solved errors below to get feedback if I did anything wrong.</p>
  
  <p><strong>First Error</strong>: No action was found on the controller 'X' that matches the name 'some-action'
  <br/><strong>Solution</strong>: Added <code>config.MapHttpAttributeRoutes();</code> to WebApiConfig.cs <code>Register</code> method.</p>
  
  <p><strong>Second Error</strong>: System.InvalidOperationException The object has not yet been initialized. Ensure that HttpConfiguration.EnsureInitialized() is called in the application's startup code after all other initialization code.
  <br/><strong>Solution</strong>: Added <code>GlobalConfiguration.Configure(WebApiConfig.Register);</code> to Global.asax.cs <code>Application_Start</code></p>
  
  <p><strong>Third Error</strong>: System.ArgumentException: A route named 'MS_attributerouteWebApi' is already in the route collection. Route names must be unique.
  <br/><strong>Solution</strong> = ?</p>
  
  <p>I've already tried cleaning and deleting all DLLs from bin folder according to <a href="https://stackoverflow.com/questions/10986909/a-route-named-x-is-already-in-the-route-collection-route-names-must-be-unique">this post</a>.</p>