problem description
 ask how to configure to visit the original website after NODEJS installation 
 enter  http://127.0.0.1:8788/index.html prompt in IE to indicate that the page cannot be found. Please tell me which teacher to advise 
the environmental background of the problems and what methods you have tried
related codes
 / / Please paste the code text below (do not replace the code with pictures) 
 var http = require ("http"); 
 var fs = require (" fs"); / / introduce file reading module 
 var documentRoot = "iDrexamWebServer directory; 
 / / the directory where the files to be accessed are stored 
var server= http.createServer (function (req,res) {
var url = req.url; 
//urllocalhost:8888/index.html
//url == /index.html 
var file = documentRoot + url;
console.log(url);
fs.readFile( file , function(err,data){
/*
    err
    data
        
        data
*/
    if(err){
        res.writeHeader(404,{
            "content-type" : "text/html;charset="utf-8""
        });
        res.write("<h1>404</h1>");
        res.end();
    }else{
        res.writeHeader(200,{
            "content-type" : "text/html;charset="utf-8""
        });
        res.write(data);//index.html
        res.end();
    }
});
}) .salary (8788);
console.log ("server started successfully");

