ASP.NET Web API Error: No HTTP resource was found that matches the request URI

Question

I am trying to add the Web API to an existing ASP.NET MVC project. This was originally a ASP.NET MVC 2 web site that was later upgraded to MVC 3 and then again to MVC 4 using the following procedures:

Upgrading an ASP.NET MVC 2 Project to ASP.NET MVC 3

Upgrading an ASP.NET MVC 3 Project to ASP.NET MVC 4

My Api controller is pretty straightforward. Actually, it is the default template:

public class ValuesController : ApiController
{
    // GET api/values
    public IEnumerable<string> Get()
    {
        return new string[] { "value1", "value2" };
    }

    // GET api/values/5
    public string Get(int id)
    {
        return "value";
    }
}

I've added a class to register de API routes.

public static class WebApiConfig
{
    public static void Register(HttpConfiguration config)
    {
        config.Routes.MapHttpRoute(
            name: "DefaultApi",
            routeTemplate: "api/{controller}/{id}",
            defaults: new { id = RouteParameter.Optional }
        );
    }
}

That is called from Application_Start

protected void Application_Start()
{
    AreaRegistration.RegisterAllAreas();

    WebApiConfig.Register(GlobalConfiguration.Configuration);
    RouteConfig.RegisterRoutes(RouteTable.Routes);
}

However, when I try to access 'localhost:50315/api/values', I get the following error:

<Error>
<Message>
    No HTTP resource was found that matches the request URI    'http://localhost:50315/api/values'.
</Message>
<MessageDetail>
    No type was found that matches the controller named 'values'.
</MessageDetail>
</Error>

According to the Routing Debugger, the route seems to be working properly, the web api route is the first entry that 'Matches Current Request'.

Answer 1

Please see below steps - it may not be give you a right answer however it will give you a direction to debug problem. You can perform these actions one by one.

1. Make sure that you have executed the following:

   Install-Package Microsoft.AspNet.WebApi
   

This is just to ensure that you have right DLLS.

2. Another thing that you can try with is add a route on the top of a get.

   class ValuesController : ApiController
   { 
       [System.Web.Http.Route("api/values")]
       public IEnumerable<string> Get()
       {
           return new string[] { "value1", "value2" };
       }
   
       public string Get(int id)
       {
           return "value";
       }
   }
   

3. Disable MvC route for debugging. i.e.

   protected void Application_Start()
   {
       AreaRegistration.RegisterAllAreas();
       GlobalConfiguration.Configure(WebApiConfig.Register);
   }
   

4. Enable GET Verb.

I am giving you below from my project as a reference.

 <httpProtocol>
      <customHeaders>

        <add name="Access-Control-Allow-Headers" value="*" />
        <add name="Access-Control-Allow-Methods" value="*" />
      </customHeaders>
    </httpProtocol>
    <validation validateIntegratedModeConfiguration="false" />
    <handlers>
      <remove name="WebDAV" />
      <remove name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" />
      <remove name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" />
      <remove name="ExtensionlessUrlHandler-Integrated-4.0" />
      <add name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness32" responseBufferLimit="0" />
      <add name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness64" responseBufferLimit="0" />
      <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
    </handlers>