I have also heard that you cat leaves his scent when he scratches and that WASHING that sent off will help. I have tried "No Scratch" spray and it didn't work. I haven't tried the bitter apple. He, however, only likes to scratch on horizontal surfaces, so only our carpet is suffering. We put folded over duct tape on his favorite spot and it has really helped. Also, try to play with your kitty ON the post (put it down horizontally). He may realize that he likes the feel of it the post. Don't forget to reward him when he does it right! Good luck!