Press the power key and hold it if the screen of your Zumo is frozen. Keep holding the power key while pressing the key that has a plus symbol ("+") on it. This will reset your device and unfreeze the screen. You can also try calibrating the screen by pressing the power key for one full minute.
If this does not work, please follow these steps.
1. Update the internal disk software. Download and install WebUpdater on the computer. Please visit this link
to download the WebUpdater.
2. Open WebUpdater on the computer.
3. Connect the Zumo 550 to the computer with its USB cable.
4. WebUpdater will automatically search for updates.
5. Follow the prompts to download any pertinent updates for the Zumo 550.
Hope it helps.
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