Dark Mesh (Lightmap problem)

Hi,
When I bake lightmap some pieces turn to dark in my scene.
e.g.

Other windows normal. Only this window getting dark.

I’m using Unity 5.3.0f4. Any idea?

Thanks

Change sun rotation and rise the number of texels, set ambient occlusion to 5 and set default parameter in general GI to High Resolution. Maybe it help;)