Hmm, I don't want to be too quick to jump to conclusions, but after about 3 hours of on and off trying to get it to work, I've ended up calling XBox Support to check the code with them, and they've told me that it isn't valid. He has been in constant communication though, giving me a few bits to try and he even checked the code for typo's etc but there weren't any as far as he could see. I really don't want to tar his good reputation, so I'm gonna hold off on saying I've been conned for now. I just hope there is a mistake somewhere and that it can be resolved by him asap as I want my Live service back again.