Boss BR-900CD Owner's Manual page 174

With Windows
9. Press the BR-900CD's [EXIT].
The USB screen returns to the display.
* If you press [EXIT] without quitting the connection to the
computer, the following screens appear. In this case, pressing
[ENTER] returns the USB screen to the display.
fig.06-106ad
10. When backup of the data is complete, press [EXIT] to
return to the Play screen.
At this point, you can safely disconnect the USB cable
from the BR-900CD and the computer.
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