Hello, have you tried transfering some or all of the music files on the disc to the music folder? the sandisk usb have a document folder which is divided into four other sub folders .1 downloads 2 music 3 pictures 4 videos. Iwas having the same problem and after doubleclicking on the document folder i was able to drag some of the existing files into the music folder and it was after doing this i was able to add more files to my usb.
IT WORKS !!1, TRY THIS INSTEAD.
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This topic has been moved from the section Forum Feedback to section Storage by Tecmo34