You need a piece of software called "AMV Convert Tool 3.68" (do a Google search for it...). This all assumes you are running a standard PC with Microsoft Windows as the operating system... Before you begin, backup anything you want / need from the player (i.e. copy and paste all the files you want to keep from the player onto your pc... Formatting will wipe all files from the player!). Once installed on your PC, with the player turned on and attached with the USB, run "MP3 PLAYER DISK TOOL" from the program group in the start menu. When the tool loads, select "low" in the format type, then select the "partition and encryption" tab at the top of the window. Firstly you must drag the slider all the way to the right, and click "start", formatting the drive... Then drag the slider all the way to the left, and again click "start", this time formatting to the correct true capacity the player has... The player will now run with much more stability, and with it's true capacity being recognised by Windows...