Hard Reset / Factory Reset will restore your device to its initial state and will delete all your files. It is advisable to back up your important files before doing the reset process.
Hard Reset:
Step 1. Turn off your phone.
Step 2. Press and hold together Volume Up + Power button for 5-7 seconds.
[Continue reading...]
Hard Reset:
Step 1. Turn off your phone.
Step 2. Press and hold together Volume Up + Power button for 5-7 seconds.
Step 3. Release the buttons when you see an Android icon, to enter Update (Droidboot) Mode..
Step 4. Select "Factory Reset" by using Volume buttons, and Power button to confirm.
Step 5. Then choose "Yes -- delete all user data".
Step 6. Confirm operation "reboot system now".