In hammer, there is no brush there, but ingame it can be seen. By that I mean ONLY seen, portals go through, you go through, objects go through. I don't know why it is there.

I've heard of this happening to some people. It's a strange kind of bug. Not sure of a solution though.

wow. looks freaky. can you stand in top of it?

That's happened to me once before, I saved as a new file, restarted Hammer, and it went away. =)

nice. so there is a solution. ill remember this if this happends to me. wich reminds me once i coulnt load my map in hammer it said some error so my map was broken. vmex is a great tool if you doesnt use to steal maps. only to decompile your own maps if the vmf are broken =)

I'll try re-saving the file as soon as I can.

It almost looks like you drew a block brush with 0 height, so Hammer only draws one face of the brush (even though you didn't). Reminds me of using the old QuArK editor for the Q1 engine. You had make each side (or face) of a brush until they got smart enough to add a block as a kind of prefab. Guess that's why I didn't get too far with that editor. Let us know how the renaming works out.

Planar glitch, recompile and it will be fixed as other have said.

yep, that fixed it.