(urgent help needed) failed to build mask for shadow culler errocode 3

For me, It was because the near clip plane on my camera was too low. It was set to 0.01 when it was showing the error. After changing the value to about 0.05, It was working for me and there was not any errors. I have no idea why changing the near clip plane fixed the error. Hope this helped.

The only way around I have, is to toggle off the lighting button in the scene view. It'll be different to what the game camera sees of course, but it worked for me.

I am also having this error. Only when using the Shader Forge editor. Any Luck?

Same error here. What the heck is that?

In my case it was the opposite to what unity_... experienced, I accidentaly set my far clip plane to 100k units instead of 10k units (to have some atmospheric effects being rendered by the camera), setting it to 10k solved this problem, which was causing a hard crash on the target platform.