In order to hard reset a ZTE F100, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
ZTE F100 device will be brought back to the default configuration of a brand new device.
1. Turn on the phone with a press of a Power button.
2. Open phone's Dialer and type in this code: *983*22387#
3. Select Yes to begin the Factory Reset. Wait for the phone to reset and restart.
4. Done!