help with terrain vanishing

[Mattitude]

hi this is my first post ;) iv just recently started useing the unreal Ed and iv found out how to make terrain but when i substact a cube as sort of like a corridor to the rest of the level iv made the whole of my terrain vanishes it does the same when i subtract a cube thats nowhere near the box with my terrain in aswell

[Fordy]

Have you tried rebuilding the level when you have finished adding/subtracting BSP geometry?

[Mattitude]

ahh ha no i knew it would be somthin stupied that id forgot to do

[Mattitude]

right iv tried that and its still doing the same thing doesnt matter where i subtract a cube my whole terrain dissappers even after iv built all the geometry