A Master Reset is the last resort for troubleshooting. This reset erases all data and restore preferences to factory default specifications. Performing a Master reset is only recommended when the existing data has been backed up or is unwanted.
From the main screen, press OK to choose MENU.
Select Settings & Tools then press OK.
Select Phone Settings then press OK.
Select Security then press OK.
Enter the phone lock code. (The default code is the last 4-digits of the mobile number).
Select Restore Phone then press OK.
Enter the phone lock code. (The default code is the last 4 digits of the phone number).