You must do this while your storage device is connected. When you delete a file from your USB flash drive on a Mac, it goes to a special hidden directory on the drive and stays there until you empty the Trash. The first and most common way to fix this problem is to ensure your Trash has been emptied in Mac OS X. Of course, this doesn’t quite add up to my flash drive’s full size so clearly something I can’t see is there taking up space. After a while you might not be able to take full advantage of your flash drive’s full capacity, because these unwanted files are taking up space.įor example, if I have a 4GB drive and I only have about 1.5GB of usable data on it, I might only have about 750MB of free space left. Both operating systems routinely create hidden files, and items you thought you deleted may still be there after all. Sometimes, though, a particular brand or model will not play nice when you frequently connect it to both Windows and Mac systems. Nearly everyone has a USB flash drive for portable data storage nowadays, and for the most part they work with almost any computer effortlessly.

Reclaim lost storage space by getting rid of the hidden files and junk that accumulates on your USB flash drive over time.