Problem previewing page on realtime preview

I am running dreamweaver 2017 and when i try to preview on real-time preview i get all browsers coming blank. Have tried clearing cache and no luck. can anyone help am stuck for days. on chrome it shows this error:

Failed to load resource: the server responded with a status of 404 (Not Found)

Then on Jquery:

15 Adobe Systems Incorporated.  All rights reserved. */

/*global $, console, URI, unescape*/

/*jslint regexp: true nomen: true, plusplus: true, bitwise: true, vars:true*/

function DevicePreviewUtils() {

    'use strict';

    this.createAjaxOptions = function (type, host, location, query) {

        var formedUrl = host + location,

            key,

            uri = new URI(formedUrl),

            options;

        for (key in query) {

            if (query.hasOwnProperty(key)) {

                uri.addSearch(key, query[key]);

            }

        }

        options = {

            'type': type,

            'url': uri.toString()

        };

        return options;

    };

    this.doAjaxGetRequest = function (host, location, query, successCallback, errorCallback) {

        var ajaxOptions = this.createAjaxOptions('GET', host, location, query);

        $.ajax(ajaxOptions).fail(function (jqXHR, textStatus, errorThrown) {

            // We got an error trying to run the work not sure what to do here

            console.log("call Failed!!  "  + textStatus);

            errorCallback.call(jqXHR, errorThrown);

        }).done(function (data, textStatus, jqXHR) {

            console.log("call succeeded!!");

            console.log(textStatus);

            successCallback.call(jqXHR, jqXHR.responseText);

        });

    };

    this.getAccessMethod = function () {

        var uri = new URI(window.location);

        return uri.search(true).m || '';

    };

    this.getDwSocketAppUrl = function () {

        return window.preview.config.DW_SERVER_PROTOCOL + '://' +

            window.preview.config.DW_SERVER_HOST +

            (window.preview.config.DW_SERVER_PORT ? ':' + window.preview.config.DW_SERVER_PORT : '');

    };

    this.convertPathArrayToString = function (pathArray) {

        if (!pathArray) {

            return '';

        }

        var path = '',

            index = 0;

        for (index = 0; index < pathArray.length; ++index) {

            var editedPath = pathArray[index];

            if (editedPath && editedPath.indexOf('DP_CLIENT_SOCKET_ID') !== -1) {

                editedPath = editedPath.replace('DP_CLIENT_SOCKET_ID', URI.encode(window.preview.socketApp.getSocket().id));

            }

            path += this.getDwSocketAppUrl() + editedPath;

        }

        return path;

    };

}

window.preview.utils = new DevicePreviewUtils();