I purchased a C41-500 client from a 3rd party to add to my current system (HR54-200 currently with one client). It works great as long as I set it up to replace my existing client. I've called DirecTV 4 times, plus I've had a technician come to my house all who provided zero help. It cannot be that difficult to authorize a second client as the reciever itself is activated and works fine as long as I replace my existing client. Any advice would be welcome as I'm extremely frustrated and ready to cancel my service all together.