[. . . ] Charge You cannot charge the battery when the the battery in an ambient temperature of 5 °C (41 ºF) to 35 °C (95 ºF). The USB connector on your Walkman is not connected to a USB connector on your computer properly. [. . . ] You can transfer songs to your Walkman using Windows Media Player 11 or 12 on your computer. If you use Windows Media Player 10 or older on your computer, install Windows Media Player 11 from the Windows Media Player download site. After the install wizard is completed, the WALKMAN Guide shortcut appears on the desktop of your computer. You do not need to re-import songs that have previously been imported to Windows Media Player 11 or 12. If you format the Walkman in Windows Explorer accidentally, do it again on the Walkman. If you format the memory of your Walkman accidentally, download the User Guide (HTML document) from the web site mentioned in "For the latest information. You can start the WALKMAN Guide from the [Start] menu (displayed by clicking [Start]). Installing the bundled software (user guides included) automatically makes a backup copy of the [Setup. With the backup file, you can install the software on another computer even after deleting the [Setup. exe] file and the [Install] folder in the [Backup] folder to the Walkman. Then, connect the Walkman to another computer on which you want to install the software and follow the above procedure from step 2. The backup data is preserved in the following [C] drive on your computer by the default install setting. [. . . ] Connect your Walkman to your computer, and then delete any unnecessary audio files using Windows Media Player 11, 12 or Windows Explorer. When you use your Walkman for the first time, or if you have not used the Walkman for a long time, recharge it fully. [. . . ]