Need help with an annoying error

[Eshy]

I've been trying out Hammer for the past couple of hours, and now the map changes I make aren't there. I was getting this error:
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (-3080.000000, 3080.000000, 65552.000000))
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (2056.000000, 3080.000000, 65536.000000))
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (0.000000, 2048.000000, 65536.000000))
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (2056.000000, 2048.000000, 65536.000000))
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (2048.000000, 3072.000000, 65536.000000))
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (2048.000000, 2048.000000, 65536.000000))
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (2048.000000, 2048.000000, 65536.000000))
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (0.000000, 3072.000000, 65536.000000))
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (2048.000000, 3072.000000, 65536.000000))
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (1024.000000, 3072.000000, 65536.000000))
WARNING: BSP node with unbounded volume (material: <NO BRUSH>, near (1024.000000, 3072.000000, 65536.000000))
WARNING: BSP node with unbounded volume (material: CUSTOMDEV/DEV_MEASUREGENERIC01RED, near (2048.000000, 2048.000000, 65536.000000))

does anyone know what this means and how to fix it?

 

[Pinsplash]

somehow, you've made brushes which hammer thinks go on for infinity. most of them are apparently going upwards for 65000 units, which is like four times the height hammer allows. you'll have to bring those brushes back down to earth somehow

 

[Tumby]

Make a new VMF and copy paste everything into that new VMF. You are most likely unable to select any of the broken brushes, so they won't be copied.