ZBrushCentral

Del Hidden button disabled

I have deleted layers, tried it in lowest and highest subdivision layers but it Del Hidden button is still disabled. Any other ideas?

You have to hide parts of the mesh before that is possible.

Yes, I know that, but there is something else. I used that function successfully before.
When I test it on a cylinder it works. And I notice, that this button is enabled and clickable in cylinder scene even when no part of the mesh is hidden, but on my object button is disabled.
Any other suggestions?

Sounds messed up. You on Windows(X) or a Mac(X) and what version of ZBrush?

I am on Windows 7 and ZBrush 4R5