Hard Reset SAMSUNG I415 Galaxy Stratosphere II

1. Power off your phone.
   
2. Then remove SIM and SD card from your phone.
3. Next press and hold Volume Up + Power button until the Samsung logo is appear.
   
4. Now press the Volume Down button to browse to option "wipe data/factory reset", and confirm with Power button.
   
5. Afterwards press Volume Down to scroll to "Yes - delete all user data", and confirm that with Power button.
   
6. Press Volume Down button to scroll to "wipe cache partition", then confirm it.
7. After wipe is complete, press Power key to select "reboot system now".
   

WARNING !
Hard Reset will erase all of your data
All described operations you are doing at your own risk.