I talked with Microsoft today and, yes, the person who answered stated that there are NO replacements for the receiver, and I would have to buy a new set up. After asking to talk to someone who had some technical knowledge and getting no where, I asked for a supervisor. I was on hold for several minutes, but I was not going to give up. Finally a supervisor answered and after explaining that I knew something about computers, he offered to send me a whole new unit, free of charge. And to top that off, he said he would expidite the order and it would ship to me in 1 - 3 days.
The number that I called is 800-360-7561, option 2. Make sure that you ask to talk to a supervisor, as the people that answer haven't a clue. They just read off of a script. I hope that this helps someone out there. Microsoft wants to keep their ccustomers and WILL do what it takes to keep them.
Have a great day.