I use Blender 2.75.1, in the last part of this lesson, the "reflection" is failed, is this a Blender bug or I have missed...

I use Blender 2.75.1, in the last part of this lesson, the "reflection" is failed, is this a Blender bug or I have missed something?
  • Kent Trammell replied
    How do you mean it's failed?
  • Tom Sun(tomjpsun) replied
    OK, I did not set the environment picture and get a whole white reflection in the Gizmo center ball, now its OK, thanks!