In order to hard reset a Ericsson S 868, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
Ericsson S 868 device will be brought back to the default configuration of a brand new device.
1. For starters, power up your phone.
2. Using Yes button to select options, open Settings and start Master Reset.
3. Now type in the phone's lock code (0000, unless changed by the owner).
4. Complete the hard reset by pressing Yes to confirm the process.