Having trouble opening Word, Excel files in mid-September 2013?

The round of Windows updates which went out 9/11, 9/12, 9/13 triggered a phantom Office installation.  Remove it and the problem is fixed.   Control Panel –> Programs and Features or Uninstall a Program and look through the list.  The first Office listed is probably dated 9/11 or similar – remove it and you will be all set.