I suggest you attempt to reset the device which should bring back default settings. If you wish to do a reset, go to Device Menu, go to Reset Settings, click + to select start then click OK.
• Windows: The voice recorder is recognized and displayed in the [My Computer] folder with the model name as the drive name. If there is a microSD card in the voice recorder, it can be used as the [Removable Disk].• Macintosh: The voice recorder is recognized and displayed on the desktop with the model name as the drive name. If there is a microSD card in the voice recorder, [NO NAME] is displayed. • For information on the PC's USB port, see the PC's user manual. • Use the optional USB extension cable (KP19) if needed