In order to hard reset a HP iPAQ hw6515, 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 hw6515 device will be brought back to the default configuration of a brand new device.
1. Switch off the device.
2. Hold down both Reset and Power buttons for, say, five seconds.
3. Device should now reset and restart.