[Solved] Getting properties from JsonResult on the JS side inside jquery ajax

How do I get the error message out of it on the jquery side?

Since you are returning a JSON object that comes with 200 status code the error callback will never be executed. So you could use the success callback in this case:

success: function(result) {
    if (result.ErrorMessage) {
        alert('some error occurred: ' + result.ErrorMessage);
    }
}

Or if you want the error handler to be executed make sure that you set the proper status code in your controller action:

public ActionResult Foo()
{
    Response.StatusCode = 500;
    return Json(new { ErrorMessage = message });
}

and then:

error: function (jqXHR) {
    var result = $.parseJSON(jqXHR.responseText);
    alert('some error occurred: ' + result.ErrorMessage);
}

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