Make request POST angular 1.x using 'Content-Type': 'application/json' : Previously I used the following type of headers in my function to make the request from the application:

###Html 

    <label class="item item-input">
                        <i class="icon ion-person placeholder-icon"></i>
                        <input type="text" placeholder="Usuario" ng-model="usuariotxt">
                </label>

            <label class="item item-input">
                    <i class="icon ion-key placeholder-icon"></i>
                    <input type="password" placeholder="Contraseña" ng-model="passwordtxt">
            </label>

###Data Login

    datos = {
              Usuario: $scope.usuariotxt,
              Password: $scope.passwordtxt
            };

`'Content-Type': 'application/x-www-form-urlencoded'`

###function

     function Autenticacion(datos) {

        
        var url = 'http://API_URL';

        return $http.post(url, $httpParamSerializer(datos), {
            headers: {
                'Content-Type': 'application/x-www-form-urlencoded'
            }
        });

    };

Now the content-type must be different from how you submitted the request in advance

`'Content-Type': 'application/json'`

function Autenticacion(datos) {

        //var url = 'API_URL';        

        return $http.post(url, $httpParamSerializer(datos), {
            headers: {
                'Content-Type': 'application/json'
            }
        });

    };

But using the ARC tool, the request works perfectly

[![Image Link][1]][1]

The server is in Azure, this the information 

    Cache-Control: no-cache
    Pragma: no-cache
    Content-Length: 270
    Content-Type: application/json; charset=utf-8
    Expires: -1
    Server: Microsoft-IIS/8.0
    X-Aspnet-Version: 4.0.30319
    X-Powered-By: ASP.NET
    Set-Cookie: ARRAffinity=0a3517ba6ed8bb14ffe517099672a3eb4ea3c4b710ad8c6e0edaa70c2d244335;Path=/;Domain=apipedroupc20170125045931.azurewebsites.net
    Date: Tue, 28 Feb 2017 20:53:09 GMT


The following errors em appear in the chrome console


    OPTIONS http://API_URL 405 (Method Not Allowed)
    
     XMLHttpRequest cannot load http://API_URL. Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource. Origin 'http://192.168.1.9:8100' is therefore not allowed access. The response had HTTP status code 405.

  [1]: https://i.stack.imgur.com/0lWZh.png