Cats are creatures of habit, and other people have told me their cat didn't take to the automatic box- I think there must be some feel to it that puts them off. Google litter box training and start from square one. He just might not do it. I suggest Feline Pine- clean smelling, lasts longer than clumping, very healthy, cheap.
Make it pleasant for him. On clean liter sprinkle some cat nip or put in his favorite toy. Offer him some privacy and locate Catbox in a pleasant spot.