Weird rectangular Smoke Shadows

Hi, I have some weird rectangular shadows when rendering a smoke scene:

The shadow appears in the area where the adaptive smoke domain is.

How can I fix this?

Smoke has a shadow in the real world

I’m sorry, I meant that dark rectangle. That should not be there and always exactly matches the area of the smoke domain.

Try moving your domain slightly down. the faces of your domain and ground plane appear to be in the same space.