Dog still poops in house?

Have you tried crate training him at night? With crate training they learn that they CAN hold it. Also, when you take him outside at night, leave him out there until he goes. This way, he learns whining ONLY means he has to go out, and going out ONLY means he has to go potty. I would get him checked by the vet if none of this helps. And also, try making his last meal as early as possible. If he's empty, he might not feel the urge to poop.