Same happened to me, no code so couldn't program new fob and stuffed if I lost the one I had. You can send the box off to Toad or I think if you can take it to an approved installer they might be able to supply the serial to Toad and get your code.
I think tho you have to send it.
I just bought a second hand brain which came with a fob and code and just swapped the brains over and reprogrammed the fobs.