If you need to have the drive be able to be cross platform you need to get a drive utility that will allow you to format the drive in FAT32 without the MSFT issued limit of 32GB. I have many drives formatted in FAT32 that are WELL above the 32GB that they say is the limit (like 1TB). I don't know of a Mac utility that will do this but SwissKnife will do it very well on a PC.
You will loose some performance, but if you need to have MAC and PC read and write to the drive then its what you have to do. You will also loose the ability to use the drive as a Time Machine backup.
Some food for thought. You may be a mac only guy and not need this but i thought that this might help someone that is in a similar situation.
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