Can't see static mesh in Top viewport (not 'W' problem)

[Maffew]

Hi everyone,

I'm having a problem with my Top viewport. I can only see certain static meshes. Some show up but others don't

Screenshot

It has been working for weeks but just decided to give up on me this afternoon.
I've tried "Unhide all"

[Maffew]

Is there some sort of Backface Cull option in UDK? If so... this is probably the issue.

[Maripon]

In every Material there is a checkbox "two-sided". Maybe that's the problem? Try checking it for the material you applied.
Hope it helps!

[Graylord]

You somehow seem to have exited any form of a rendering mode, try wireframe, unlit, lit etc.