Before you give your handset to repair shop or buy new handset, please try the following procedure to repair your device. First charge your battery more then 70%, backup your important data like phonebook, message, email, images and settings and in most cases take out SIM card and SD card. After doing hard reset not possible to recover your data, so online backup is always important. For all of your data, a backup should be done on a external device, hard drive, raid system media or SD card.
- Press and hold Volume UP + Power key it will show fastboot recovery in green screen.
- continue press and hold don't leave the keys until it shows recovery in red screen.
- as soon as red screen appears press home key and android logo will come.
- select wipe data/ factory reset and press power key to confirm
- now select yes -- delete all user data press Power key to confirm.
- now reboot device.