I have a memory stick I've been using to transfer midis and patterns from my computer to my Audya synth for some time but recently it won't let me put anything on it from the computer and I get this message:

"The root of drive E:\ is formatted with the FAT file system can only hold a limited number of items. Store the items in a subfolder, or reformat using the NTFS system"

The stick is only about 10% full and I haven't done anything to it that would cause it
to not work.

Any ideas?