I haven’t used my DxO ONE in a long time. The battery seems dead and the OLED display stays off even when I plug the camera into a charger. How can I restart my DxO ONE?

To restart your DxO ONE: 

1. Plug the DxO ONE into a USB wall charger and have it charge for at least 2 hours, even if the OLED stays OFF.
2. After the DxO ONE has charged for 2 hours or more, unplug it from the charger.
3. Push the RESET button.
4. Plug the DxO ONE into a USB wall charger again. The OLED display should turn on and the DxO ONE will then be charging in standard mode (rather than in slow mode).