Sony WALKMAN NW-WM1A Help Manual page 5

The computer does not recognize the microSD card in the Walkman.
The Walkman does not recognize a microSD card.
Media Go
Media Go cannot be installed on a computer. Installation of Media Go fails.
Media Go does not recognize the Walkman.
Playing Music
The Walkman cannot play transferred content.
A track is duplicated on the Walkman.
Others
You have spilled liquid (water, coffee, etc.) on the Walkman.
You have washed the Walkman in a washing machine.
The Walkman does not work properly.
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