Why is my mesh not blocking Light?

Graphics
1

I have a mesh object with a Material and Mesh renderer which is set to cast shadows.
I am shining a Realtime spotlight on this object. This light is also set to cast shadows.

My camera is set to Deferred.

But my mesh does NOT seem to be blocking the light. Why?

2

Maybe take a screenshot of the inspector with the object selected, so we know the settings look ok, and maybe somebody can suggest some changes to try.