[Error] "Maps need lighting rebuilt."

[anonymous_user_5ed114a5]

I had suffered this problem from foliage, InstancedStaticMeshComponents as well.
However have found a solution to fix it in 4.7.6.

1. Open ‘World Settings’.
2. Goto ‘Lightmass’ category.
3. Check ‘Force No Precomputed Lighting’.
4. A popup will appear. Press ‘OK’.
5. Press ‘Build All’ or ‘Build Lighting Only’. Static Lighting will be crack. That’s OK.
6. Save the map.
7. Reload the map. Open another map and open the map or double click the map in content browser.
8. Lightmaps will be 0 in Lightmass categoty. If not, load the map again.
9. Uncheck ‘Force No Precomputed Lighting’.
10. Save the map.
11. Press ‘Build All’ or ‘Build Lighting Only’.
12. Solved.

!! You are amazing. Thank you !