Please help with potty training tips for my adult dog!

Question
about 7 month's ago I adopted a min-pin mix from the pound.  He (Norman) is the sweetest little dog.  HOWEVER we can not seem to housebreak him!  We already have a Chihuahua mix who is fully housebroken.  We have a doggie door that both dogs use constantly, we never close it, they go in and out all day long.  Norman at first pooped and peed indoors but now it is only pee.  And he only goes in three specific places in the house.  It is so frustrating, I try and keep a very watchful eye on him but he will go outside and spend 2 hours out back, come straight in and pee in one of his spots!  We had the carpets professionally cleaned to try and get the smell out so he would stop going to those spots but the guy told us it is no use that there is to many spots in the same area, that he couldn't get it all out.  I have tried all the potty training tips and nothing seems to work!  I just love him but he is ruining my carpet, I don't want to get rid of him but I can't afford to re-carpet my house either!  Any advice is greatly appreciated!!

Answer
The problem with doggie doors is they do not teach a dog anything; they just allow access to and from the house. YOU need to housebreak this dog; you must pretend that you just brought home a brand-new puppy.

He must be confined in a crate when he cannot be watched, and he must go outside after eating, sleeping, and playing (in the house). You must go outside with him when he needs to potty so that you can SEE that he has gone and you can praise and reward him for doing so. You must limit his access in the house, and definitely keep him away from his chosen potty areas.

Only have him outside long enough to potty. Leaving him outside for a long time only confuses him as to the proper potty area, particularly if he is napping and playing out there. Most dogs do not want to potty where they sleep and play.

The other thing you might do is have him examined to make sure that he does not have a bladder infection that could be causing this problem.

http://www.inch.com/~dogs/housebreaking.html