Hard reset the Verizon HTC Thunderbolt smartphone if you wish to wipe all data from the memory of the device. A hard reset (also known as a factory reset) will wipe all data from internal memory and set the phone back to factory default settings. Follow one of the 2 options below.
Using software menus
1. Open Settings.
2. Select SD card & phone storage.
3. Choose Factory data reset.
4. Touch Reset phone.
5. Select Erase everything.
Using hardware buttons
1. Turn the phone off by pressing and holding the Power button for two seconds and selecting Power off.
2. Press and hold the Volume Down button, then press and hold Power.
3. Continue to hold both buttons until you see the Android logos appear on the screen.
4. Press Volume Down to toggle to the Factory Reset option, and select it using the Power button.
The Thunderbolt will then hard reset and take a few minutes to complete.