Why can't connect to socket.io-client with ubuntu via node js?

Question

Node.js

On windows, I connect to the server through node js using socket.io-client and everything goes well. But - when I drop the script on ubuntu, I can't connect, while - the versions of the node and the socket.io-client package are the same (I even dropped them from windows to ubuntu). When I try to access the site using links, I get a 403 error, while the site works if you access it from windows. It may be possible somehow with the help of debugger to find out what's wrong?