Hi ashley_rb,
Try the
Format Utility for USB Devices from -->
here.
It's a format utility for USB devices.
Otherwise try formatting from Windows Explorer as well to see if that helps.
Last resort, if memory is hacked, it will ERROR (as the memory space doesn't actually exist, it won't copy the full file across, just a 'ghost' of it) when trying to use the file or accessing the file from your computer. So fill your player to the max, then make sure you can access/open all the files on it.