 <p>A problem I ran into was related to the ordering in Application_Start(). Note the order of Web API configuraton below:</p> <p>This does NOT work</p> <pre class="lang-cs prettyprint-override"><code>protected void Application_Start() { AreaRegistration.RegisterAllAreas(); FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters); RouteConfig.RegisterRoutes(RouteTable.Routes); BundleConfig.RegisterBundles(BundleTable.Bundles); GlobalConfiguration.Configure(WebApiConfig.Register); } </code></pre> <p>This does work </p> <pre class="lang-cs prettyprint-override"><code>protected void Application_Start() { AreaRegistration.RegisterAllAreas(); GlobalConfiguration.Configure(WebApiConfig.Register); FilterConfig.RegisterGlobalFilters(GlobalFilters.Filters); RouteConfig.RegisterRoutes(RouteTable.Routes); BundleConfig.RegisterBundles(BundleTable.Bundles); } </code></pre>