I have encountered a bug with the material preview -I cant decide if it is the same problem as that isaacnewton has...  anyhow this is what I reported to e-on, just in case it helps someone else: ------------- I import 2 .obj items. After the first (3ballsbottle) there is no sign of any problem. After reading the second (Cylbottle): (See corresponding section in attached file) A. The object that isnt selected turns green, The material preview window (top left corner) turns black completely (the material should be shown on a sphere, there is no sphere at all) B. I select the other material, the selected object turns red,as it should, but the other turns green. Preview window is black. C. I open the material editor, The preview window in it (top part) is a black square. The color production preview is correct. (it's the default material). D. I click x to close the material editor, without changing or saving anything, now the material preview in the top corner is correct! Not only that, the material preview of the other object, which I have not edited at all, is now correct too!

Note: the scene render in the little window in the world browser and any full renders I make at any stage are all correct.

PS - I am sending you the objects too but the problem is general, not just with these 2 objects. It happened with some poser objects too.

"I paint that which comes from the imagination or from dreams, or from an unconscious drive. I photograph the things that I do not wish to paint, the things which already have an existence."
Man Ray, modernist painter
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