doggie cat door problems

[melanie]

mums little man max, (6mth shzu cross) is having problems with his backdoor. they have a screen door with just a square cut out of it with no cover, he is happy to pass through this. on the actual solid backdoor they have the same thing but it has a perspex flap over it. max refuses to enter through the perspex, we have tried coaxing him through with just about every yummy snack in the world and nope, he wont budge. yesterday he was put outside for his business and no one let him back in, we just put heaps of treats behind the perspex door, absolutly nothing would get him through that door.

has anyone had this problem? any ideas??

my only idea left is to remove the perspex and have nothing, but that is not such a warm idea. and proping it up oculd cause problems if it shut while their were out.

any ideas would be great