Streaming sunlight through a window

Please help me with this problem.

I am using an ordinary direct light to shine through a fixed window with 9 panes of glass and I wish to use a volume light effect to make it look like streams of light are pouring through. I also have a sky background and when the density of the volume light as applied to the direct one is 0.8, then the sky background cannot be seen, but nonetheless I cannot create the effect of streaming sunlight,

What should I do here,
thanks Nigel :sunglasses:

Are you using the VRayEnvironmentFog as opposed to the Volume Light Effect in the light roll out?

I couldn’t replicate your error so maybe this link could help you better?

Thanks for the reply, progress to date

I am using the standard volume light effect, but hve had some succes by using the shadow map, on the direct light however I have tried to find the VRayEnvironmentFog but without success where do I go to get this? as I will give it a good go when I do

It’s in the environment and effects (press 8 ) and it will be under the environment tab within the atmosphere roll out.

here is the atmospheric pass that I made for our last project. Just follow the instruction in help that Jer25 already post and your done.