Meshes are black

Hello I have a very important model and when the lights are built, it becomes black. What can I do about it? Can I make it always unbuilt or do anything else? Please help! Thanks

Make sure it has proper light map UVs.

There is no more generate unique uv option in the mesh settings → window, why it was removed?

The automatic lightmap UV generation is very limited, it’s best to do that in your 3D software.

the model was bought a year ago, cant do much qbout it, dont own 3d max

You don’t have to use 3ds Max
But the automatic UV generation in UE4 requires that your mesh already has UV seams set up so if it doesn’t have that you can’t use it.

What should I use then? I tried googling “uv lighmap” and all result were UE related

No problem. Use Blender.