hammer error when compiling The command failed. Windows reported the error:"The syste

[PDT]

What tool textures are you using? (a screenshot of just the tool brushes would help a lot). A brush normally must be entirely covered in a tool texture for it to work properly. i.e.: an areaportal has to have all 6 sides in the tools/areaportal texture or ense it will be wonky.
Also I heard somewhere that certain tool textures don't work in TF2 and you might be using those. You'd have to ask someone else for specifics, though, because I can't remember which ones.
Other than that, I don't know what could be causing the problem.

[elmo]

I don't even know what areaportal does, all I'm using is black/playerclip/skybox/trigger brushes

I couldn't find any thing at all that fit within having more than 1 tool material on a brush.

I'll look again.

I tried going through each tool based vis group and compiling each one, none of them compile, and there is no error in any of the brushes.

Just want to give up on it all now.

[TehStoneMan]

It could be that you have accidently put a tool texture on a regular brush where you don't want it to be.