@ironsoul:

You may be right, but from the look (the shiny surface of the figure) it looks exactly like a SreeD preview. And it's easy to accidentally switch from OpenGL to SreeD - just one wrong click in the preview port...

But this can't be resurrected with a "factory state" reload because it's saved in Poser's .INI file, not the preferences.

So to go back, right-click somewhere in the preview and in the drop-down menu that appears --> check "OpenGL"