[matese]

Have you tried holding the door open from the outside and coaxing him to come through using a treat, or his fav. toy? You may have to change the door to something that does not make a noise. I had a special screen door made with a doggie door, it's not really a door, it's heavy gauge clear plastic curtain like, pup just walks through it, they can see through it. You may have to remove what you have and replace with clear plastic, if Griffy is on the skittish side you don't want to ad to it,just something to think about if he refuses to use it willingly.