My iphone 4s won't connect to itunes?

Every time I try to connect it, my iTunes freezes on the computer and later comes up saying it could not be connected and try again later. It worked the first day i got the phone and never again. I have updated my iPhone and iTunes to the latest version and it still does not work. I tried connecting it to a friends computer and it worked fine. I don't understand what is wrong, please help!

Change a new data cord.