Hi,

Trying to load my map I encountered a problem I'd never seen before
This is the error that appears in command prompt

ConVarReg gpu_level doesn't point to an existing ConVar
Brush 1098: FloatPlane: bad normal
Side 0
Texture TILE/WHITE_WALL_STATE001

I've tried quite a few things to solve the issue, but none worked.
Does anybody know how to fix this?

SOLVED
I moved the wall a bit in one direction and it got fixed.

In hammer, press Ctrl+Shift+G
Type in 1098 in the text field to find the bad brush, then use to our vertex tool to merge the unnecessary vertex to another one.
Hope this works.

If nothing helps, just replace the brush.

I had some maps where a brush was corrupt without reason (no deformation or something else). Rebuilding is the fastest way.