I get an error when I try to open my page.

Code:

var express = require ('express'),
   App = Express ()
   Server = Require ('HTTP'). CreateServer (App),
   IO = Require ('Socket.io'). Listen (Server);
Server.listen (3000);
App.Get ('/', Function (REQ, RES) {
   res.sendfile (___ dirname, '/index.html');
});

Answer 1, Authority 100%

Instead of this

res.sendfile (___ dirname, '/index.html');

Write this

res.sendfile (__ dirname + '/index.html');