If you make a brush that's too big, you will get that error. Split large brushes up into smaller ones. I've noticed keeping brushes under 4,000 units should solve this problem. I originally had a 14,000x16,184x4258 unit skybox made of 6 brushes, and got that error 6 times, one for each sky brush. I split it up in to about 25 brushes and now it works fine.

Well, call me Drunken Idiot.....

I remembered I made a test .pk3 of my map for my clan to playtest, and I remembered it was still in my CoD Main directory.

Removed it and woohoo, the new .bsp is fine....

Thanks for the tip though Glenn.....

DC