Can't build light with starter content.

There are a directional light and a cube in the level , and the light building stopped at 75%. UE 4.9.1 , preview quality.
The cube is StarterContent/Shapes/Shap_Cube. After I replaced it with some asset in StartContene/Architecture , the light building can be done very quickly.
Dose anyone know what’s wrong with this cube asset? Thanks!