Certain versions of Mac OS X may cause iPod mini (Second Generation) to not be recognized on USB
If you're using Mac OS X 10.2.7 and earlier:
To connect iPod mini (Second Generation) over USB, you must update (or upgrade) to Mac OS X 10.2.8 (the update is available from Apple Downloads or through Software Update). You must also install the software from the included CD. Make sure you are using iTunes 4.7 or later.
If you don't update your OS to a required version of Mac OS X, you won't be able to use the iPod mini (Second Generation) over USB. Without an update to the OS, you can use FireWire instead of USB to connect and sync, using the optional iPod Dock Connector to FireWire cable.
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