WebAPI: A callback parameter was not provided in the request URI - json

Question

I am executing a post method in my API using fiddler I get error "A callback parameter was not provided in the request URI.". However, this works for get method.
I have seen several answers to this question, and as per the error I need to specify a callback parameter. However, I'm not sure how to do this using fiddler.
In response to one of those answers from Can I make a jQuery JSONP request without adding the '?callback=' parameter in URL? . I've tried the following in fiddler and I get the same error..
url: http://velopoint-api.localhost.dev/api/v1/tasks?callback=foo
header:
User-Agent: Fiddler
Host: velopoint-api.localhost.dev
ContentType: application/json; charset=utf-8
Authorization: basic "UNQUOTED"
Content-Length: 47
jsonp: true
jsonpCallback: jsonCallback
dataType: jsonp
request body
{ "Title":"New Task", "DueDate":"20-jul-2014" }
Startup
public static void Register(HttpConfiguration config)
{
config.MapHttpAttributeRoutes();
// Uncomment the following line of code to enable query support for actions with an IQueryable or IQueryable<T> return type.
// To avoid processing unexpected or malicious queries, use the validation settings on QueryableAttribute to validate incoming queries.
// For more information, visit http://go.microsoft.com/fwlink/?LinkId=279712.
// Change Formater to use CamelCasePropertyNamesContractResolver
var jsonFormatter = config.Formatters.OfType<JsonMediaTypeFormatter>().FirstOrDefault();
jsonFormatter.SerializerSettings.ContractResolver = new CamelCasePropertyNamesContractResolver();
/* Support JsonP */
//register JSONP media type formatter
config.Formatters.Insert(0, new JsonpMediaTypeFormatter(jsonFormatter));
config.Formatters.JsonFormatter.SerializerSettings.ReferenceLoopHandling = Newtonsoft.Json.ReferenceLoopHandling.Serialize;
config.Formatters.JsonFormatter.SerializerSettings.PreserveReferencesHandling = Newtonsoft.Json.PreserveReferencesHandling.Objects;
...
}

Answer 1

After playing around a little, I've finally figured it wasn't actually routing to the post method.
My header is now
User-Agent: Fiddler
Host: velopoint-api.localhost.dev
Authorization: basic UNQUOTED
Content-Length: 224
Content-Type: application/json
I fixed the problem by specifying Route attribute to my Post method and passing an empty string to the pattern parameter, both on the Get and the Post (as I already have the RoutePrefix attribute specified on the class.
[RoutePrefix("api/v1/tasks")]
[VeloPointAuthorise(perUser: true)]
public class TaskController : BaseApiController
{
[HttpGet]
[Route(template:"", Name = "TaskRoute")]
public HttpResponseMessage Get(int page = 0)
{
....
}
[HttpPost]
[Route(template:"")]
public HttpResponseMessage Post([FromBody] OrganiserTaskModel model)
{
....
}