Assigning some materials for Rhino Render and get this error. I hit duplicate and it still does not switch materials. What gives?
Can you share the file or just the objects that this material is applied to? Clicking duplicate should make a new copy of the material. Also, what is the active render engine? I know you said Rhino Render but I see you have Maxwell too and just want to make sure.
It was a block instance. Doah.