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Hard reset via Settings menu

1. Slide the Notifications panel open, and then tap Settings
2. Tap Backup & reset.
3. Tap Reset phone.
4. If you also want to delete media and other data on HTC Desire 600, select Erase
5. all data.
6. Tap OK.

Hard reset via external hardware keys

1. Remove the battery, wait for a few seconds, then reinsert the battery.
2. Press and hold the VOLUME DOWN button, and then press and hold the POWER button.
3. Wait for the Lcd with the three Android images to appear, and then release the POWER and VOLUME DOWN buttons.
4. Press VOLUME DOWN to select FACTORY RESET, and then press the POWER button.

Only do this if you can not do it via Setting menu.

Performing Soft Reset

1. If the display is off, press the POWER button to turn it back on.
2. Unlock the display.
3. Press and hold the POWER button, and then tap Restart.
4. When asked to confirm, tap Restart.

Hard Reset Garmin Nuvi 600 series to Factory default settings

1. Turn power Off and unplugged from power
2. Touch and hold the lower right corner of the Lcd with an index finger or the eraser end of a pencil
3. Continue touching and holding the lower right hand corner of the Lcd then power the device ON
4. Release the power button when the device powers ON
5. You will see a new message: “Do you really want to erase all user data?”
6. Remove your finger from the touch Lcd when this message displays
7. Touch Yes