garybeafl--thanks for the response.
It does not apply to my situation. I have a Home assembled PC. No lable on the tower. I know what Product Key was used to install Win7. I also know what Magical Jelly Bean reports. They are the same.
My question was to learn how to advise people who have commercially built PC's whether MJB's Product Key or the one on the label is more likely to work. I was just echoing your Post #3.

jdc2000's post #4 is little quizzical. Does it mean that either Product Key (label or MJB) will work?