I have a 1/2 hp craftsman garage door opener. It worked fine with both remotes until we changed a battery in one of the remotes. Now only one remote will work at a time. I can get both remotes to work, but only one at a time. As soon as you add the other remote the first one will quit, and vice versa. Tried adding a craftsman keypad, same problem. As soon as the keypad is added, and starts working, neither remote will work. Add a remote, keypad stops working. Sears is of no help, they only want to send out a service tech. Any help would be appreciated!!!!!