Are you being productive in your business? In other words, are you "working your business"? Or are you "playing office"?
What does productivity mean in your business--phone calls to clients? widgets produced? accounts opened?
Whatever it is that drives your business and generates income or income potential, that is what you should be doing to be considered "productive".
If calling your cliets to set up appointments is what generates income, then re-organizing your filing system (again!) is not "productive" work.