Subtracting the object

[anonymous_user_3d3ce61e1 (anonymous_user_3d3ce61e)]

Whenever i try to subtract any object to create a door for my house it just shows an invisible projectile idk why any help?.

Link: Imgur: The magic of the Internet

it wasn’t letting me upload photo so here is the link to it.

[anonymous_user_3d3ce61e1 (anonymous_user_3d3ce61e)]

any help guys?

[anonymous_user_9f8082c3]

Try to cut and paste it again ?