I broke lighting somehow

When I create a directional light in a new project, and then add a sphere, the sphere is shaded appropriately (in the editor and at runtime).

I am using Unity 4 free. In a different project, same scenario, but when I create the sphere it’s got no shading (shaded in the editor but nothing at runtime). Can anyone
tell me what I’ve done wrong to cause this?


As requested, screenshot of a sphere that is shading:

Screenshot of a sphere that is not shading:

Both scenes have a single directional light. The non-working scene has a lot of other objects in it, if that affects anything somehow I’d love to know.

maybe a screenshot would help?

Do you change the Ambient Light somewhere in your scripts or set Materials to use Unlit/Self-Illuminated shaders?