my map's terrain just vanished?

[mabufo]

I open up the SDK, click on hammer.. open my map and... all the terrain I had is gone. Everything. I didn't save it like this or anyhthing... it's just gone. My level is an outdoor one too - so this is really ripping me a new one... I cant work on this map anymore - on account of the terrain was the heart of it.. I'll need to start a new one then..

Has this ever happened to anyone? Why would this just happen all of a sudden?

 

[Raeven0]

Did you uncheck the Displacements VisGroup?

 

[mabufo]

Yes I did, and it's gone... I have no idea what could have caused this.. could that update that had been released have caused this somehow?

 

[NonStopableForce]

When you opened it back up did it say something about a certain number of surfaces have been removed?
I got this message when i made a inforrect surface, but i saved it, and then opened it, and this message poped up.

-NonStopableForce