"Incorrect Content-Type: " exception throws angular mvc 6 application

The accepted answer didn't work for me. For me, the solution was to add a header to the $http call:

        $http({
                url: "/install",
                method: "POST",
                data: data,
                headers: {
                    "Content-Type": "application/x-www-form-urlencoded"
                }
            })
            .success(...);

In my case, adding [Produces("application/json")] did nothing, but adding the [FromBody] attribute to the parameter is what did the trick!

Hope the following examples helps you.

Try to decorate your controller with

[Produces("application/json")]
[Route("api/[controller]")]

Since you din't show your controller name I will give you a fictitious full working example

controller

[Produces("application/json")]
[Route("api/[controller]")]    
public class DashBoardLayoutApi : Controller
{
    public DashBoardLayoutApi()
    { }

    [HttpPost]
    public void Post([FromBody] LoginViewModel data)
    { }
}

C# viewmodel

public class LoginViewModel
{
    public string Email { get; set; }
    public string Password { get; set; }
}

HTML/JS

<script>
    var data = {
        Email: 'Test',
        Password: 'Test',
        RememberMe: true
    };

    $("#test").click(function() {
        $.ajax({
            url: '/api/DashBoardLayoutApi',
            type: 'POST',
            dataType: "json",
            contentType: "application/json; charset=utf-8",
            data: JSON.stringify(data),                   
        });
    }
</script>
<button id="test"> Save Layout</button>

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