McMorton

Hello I creatd a test cube with some inner elements. If I print it I can see the inner structure at the outside of the cube. In Cura I noticed that the reason is maybe that he only print one outer wall. The inner wall are seperated to print the inner structure. I think a picture tells more than my bad explanation: lock at the corner with the inner parts. Is there a way to change this? (by the way: I'm new in 3D printing. Therfore sorry if this is a stupid question)