In order to hard reset a HP iPAQ 910c, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
HP iPAQ 910c device will be brought back to the default configuration of a brand new device.
1. Turn on the phone.
2. Press'n'hold Record button + Reset button + OK button.
3. Instructions will appear on-screen. Follow them. Done!