In order to hard reset a ZTE Memo, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
ZTE Memo device will be brought back to the default configuration of a brand new device.
1. Turn on the phone.
2. Open Menu > Reset Settings > Master Reset > Security Code (the default code is 0000).
3. Voila! Done.