changing variable in promise reject

Question

var app = angular.module('login', []);
app.controller('LoginController', ['$scope', '$http', function
    ($scope, $http) {
 this.error='test';
        this.submitForm = function () {
        var params = $("#loginForms").serialize();
        $http({
            method: 'POST',
            url: '/admin/doLogin',
            data: params,
        }).then(function (response) {
            // this callback will be called asynchronously
            // when the response is available
        }, function (response) {
            $scope.error = response
            console.log(response.status)
            if (response.status == 404) {
                this.error = "Page not found";
            }

        });
    }
}]);

am trying to set the error message inside the process and bind it to view

<div id="container"  ng-controller="LoginController as lm" >
    <br>
    <div class="error" >{{lm.error}}</div>
</div>

i am trying to change the error variable in promise reject event.this is not working ,please help