Sony PCG-FXA63 User Manual page 82

Disconnecting a mouse or keyboard
You can disconnect a USB mouse or keyboard when the computer is turned on or off. Disconnecting the USB mouse or
keyboard when the computer is in a power saving mode (Standby or Hibernate) may cause the computer to malfunction.
To disconnect the USB mouse or keyboard when the computer is off
 Unplug the USB cable from the USB port on the computer.
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