Knockout.Validation problem

[Jeric John Romero]

Hi, i am new to knockout js. Im wondering what's wrong with my viewModel. I want to display my error messages in an alert button. But when it pops out.. it says it is undefined. 

Another things is, i shouldn't be displaying the error messages beside the text input of my html. I tried putting ko.validation.configure({ ... }) above my viewModel but the browser says 

undefined is not a function. What am I missing? 

There are only two input controls in my html page. 

function personViewModel() {

    var self = this;

    self.lastName = ko.observable().extend({ required: { message: 'Last name is required' } });

    self.firstName = ko.observable().extend({ required: { message: 'First name is required' } });

    var firstTabValidation = [

        self.lastName,

        self.firstName

    ];

    self.validateToNext = function () {

        var errors = ko.validation.group(firstTabValidation);

        if (errors().length == 0) {

            alert('Valid');

        } else {

            alert(errors.showAllMessages);

        }

    };

}

ko.applyBindings(new personViewModel());

[ilya...@gmail.com]

Have you included the validation plugin?

[Jeric John Romero]

I have solved this. I did try to use ko.validation.init instead of ko.validation.configure. However, I can't configure the error message to not show beside my element.