I have a 5 year old Shar Pei who has been house trained since he was 6 months old who has started pooping in the house (same place everytime) on a daily basis. He has done it once before when I brought my cat home but that passed. Nothing has changed in or around the home and I can't for the life of me figure out why he is doing this. I let him out today and we were in the yard for at least 30 min, within 10 min of being inside I get to find a lovely pile from him. HELP!!

First off, you may want to have him checked out by a vet to rule out any possibility of a health problem. Next, if there truly has been no change in routine, living arrangements, etc, then you may want to try training you dog do essentially "potty" on command. For example, after your dog has his regular meal, wait 15-30 minutes then go outside with him and tell him a command such as "potty" or "do your business", and watch him. Keep repeating it and when he does relieve himself, praise him highly and even offer him a reward such as a biscuit or small treat. If you continue to do this he'll eventually do his "duty" on command. It has worked wonders with my dog. Also, when he is inside and hasn't gone potty outside yet, keep a very watchful eye on him, even if it means confining him to a room with you so you can monitor his behavior. Each time he gets away with going in the house, it reinforces that this behavior is acceptable.