Not entirely sure all the tricks, but you have to clean/bleach the snot out of where he's gone that you don't want him to, it has to completely stop smelling like he's used it before. Reclean the litter box, possibly add a 2nd litterbox if the floor crapping and 1st box are on different levels, possibly make the area he now wants to go in smell like nutmeg if all else fails. Also, make sure he's not stopped up somehow, be it hair or urinary blockage, those can make male cats crap outside the box and neither is terribly uncommon. Our male cat does that if we don't keep him shaved down, he has more hair than he can handle. Valka'd know more.