You must have at least Mac OSX to use this USB cable. 

Mac OSX automatically loads up the driver when you plug the cable in. 
You will NOT see any indication of anything new being plugged into the 
computer after you plug in the cable.
 
Confirm that your Mac computer has properly installed the TB USB MIDI cable:
    - Goto your Mac Hard Drive 
    - Goto 'Applications' 
    - Goto 'Utilities' 
    - Click on 'Audio MIDI Setup'
In the 'MIDI Devices' tab, you should see the TB USB MIDI 1x1.
 
If you do not see TB USB MIDI 1x1, download and install the latest OSX update
(10.3.9 as of this writing) and the MIDI interface will be recognized. 
 
As long as the TB USB MIDI 1x1 shows up under MIDI devices, it means that 
the TB USB MIDI cable is functioning properly.
 
NOTE:
  Please note that the Software CD included in the package, will function
  ONLY in the Windows platform. It does not support the MacOS, therefore it
  should not be used in this environment. Any MIDI recording applications 
  MUST be specifically designed for Mac OSX. You cannot use a MIDI 
  application that is running in 'Classic' environment as there is 
  insufficient MIDI support for the latest USB devices.
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