The computer does not recognize a microSD card inserted in your Walkman.
- Change the setting to [SD card] as the storage to use.
- Make sure that no data is being transferred by checking your Walkman screen. Disconnect the USB cable from your computer, and then connect it again.
- Back up all of the data on the microSD card (not supplied) to your computer, and then initialize (format) the microSD card with your Walkman.