Building lighting does nothing

Whenever I try to build the lighting of my map UE4 just does nothing and then says lighting was build in 0:00:00.

I honestly have no clue why it does so.
Last time I built lighting (a week ago) I was still working on 4.5, but any other map (even in the same project) just builds fine in 4.7.1.

Does someone have any idea what’s causing that ?

Thanks !

One thing that comes to mind is possibly you have “Force no pre-computed lightmaps” selected in the Lightmass section of the World Settings panel. To open it up and check, on the toolbar click on Settings then World Settings, and scroll down in the details panel that opens up.

One other thing to check is the mobility of your lights, if they are all set to Movable it may prevent lightmass from building (not 100% sure on this, but worth checking into).

Let us know if that helps!


I had indeed checked “Force no pre-computed lightmaps” and completely forgot it ! Wasn’t that complicated after all !

Thank you so much !

I love you!!