Material Thumbnails with no reason now became all Black!

[jessesn (Jessesn Chen)]

@ripedro

I have been working with the latest Rhino 7, for some time. All was fine, then today, the material preview thumbs, became all black. After some trials, even doing with a brand new document, noticed that is something related with the lighting:

Pls give it a try with following solution,

R7 - Material Thumbnails All Black?

Hi @andyconnacher, There are two Rhino test commands that may fix the issue of thumbnails displaying black instead of the material preview in the Materials panel. TestRestoreLibraryFileAssociations TestClearRDKCaches Give these a try and let us know if it resolves your issue. Thanks, Mary Ann Fugier