Programmer - Novice with jQuery AJAX

Programmer Question

I am simply learing Ajax with jQuery and have a simple page method that takes in a parameter and returns a string. For some reason, I am not getting the return string but I am getting to my 'success' message:

$(document).ready(function() {
            $.ajax({
                type: "POST",
                url: "testFormMatt.aspx/sayHello",
                contentType: "application/json; charset=utf-8",
                data: '{"name": "matt"}',
                dataType: "json",
                success: function(msg) {
                    $.jGrowl('The web service has been successfully called');
                    $('#result').append(msg);
                }
            });
});

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