In order to hard reset a Mitsubishi M800, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
Mitsubishi M800 device will be brought back to the default configuration of a brand new device.
1. Welcome. Power up the phone.
2. Enter this code: *#3646633# or *#77218114# or *#94267357# or *#19912006# or *#118811# or *#3646633# or *#881188# or *#9426*357#
3. Your cellphone will now reset'n'restart.