In order to hard reset a Acer Liquid Express E320, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
Acer Liquid Express E320 device will be brought back to the default configuration of a brand new device.
1. Be so kind as to turn off the phone.
2. Now press and hold together Volume Down + Power button until the phone vibrates once.
3. After it vibrates, quickly release Volume down and press Volume up and you will see a new menu on screen.
4. While in that menu, use Volume buttons to select option "Recovery".
5. After that, choose "Wipe data/factory reset" using Volume buttons to browse options. Press Menu button to confirm operation.
* In case Menu button does not work, try to use Power button.
6. Now, confirm operation by choosing "yes - delete all data" with Menu key.
7. Finish by choosing option "reboot system now".