Socket.io event won't fire and cannot emit from client

So i was trying to set a new project with nodejs and socket.io

at first i try these codes in my home pc at this site: http://socket.io/#how-to-use

i tried the first example and it works well so i continue my work at my home pc.

but, when i try it at my work pc my work is not working.
even the first example at the web doesn't work.
the client doesn't receive the emitted 'news' event from the server
and the client doesn't emit 'my other event' to the server.
there's no error at the client browser and i already try at all browsers i use (firefox, ie, and chrome all of them are the latest version)

why does the client doesn't emit the event to server, and the client can't receive emitted data from server?

what is the problem? is it the computer at my work? because i already tried it with 3 different computer, and the result is still the same. it only work at my home pc. and at my work computer (win7 x86) i already disable my UAC and firewall.

i use nodejs v0.10.1, socket.io v0.9.13

here's the code that i copied from the example from socket.io:
client.html

<script src="./node_modules/socket.io/node_modules/socket.io-client/dist/socket.io.js"></script>

<script>
  var socket = io.connect('http://localhost:8999');

  setTimeout(function(){
    socket.emit('my other event', { my: 'emitted by timeout' }); // nothing happened at server
  },3000);

  socket.on('news', function (data) {
    console.log(data); // this won't fire
    socket.emit('my other event', { my: 'data' }); // this won't fire
  });
</script>

server.js

var app = require('http').createServer(handler)
  , io = require('socket.io').listen(app)
  , fs = require('fs')

app.listen(8999);

function handler (req, res) {
  fs.readFile(__dirname + '/index.html',
  function (err, data) {
    if (err) {
      res.writeHead(500);
      return res.end('Error loading index.html');
    }

    res.writeHead(200);
    res.end(data);
  });
}

io.sockets.on('connection', function (socket) {
  socket.emit('news', { hello: 'world' });
  socket.on('my other event', function (data) {
    console.log(data);
  });
});

output from node console:

   info  - socket.io started
   debug - client authorized
   info  - handshake authorized c3Y6q0EnyWtldKBKnUHp
   debug - setting request GET /socket.io/1/websocket/c3Y6q0EnyWtldKBKnUHp
   debug - set heartbeat interval for client c3Y6q0EnyWtldKBKnUHp
   debug - client authorized for
   debug - websocket writing 1::
   debug - websocket writing 5:::{"name":"news","args":[{"hello":"world"}]}