Samsung Galaxy S 4G hard reset
phone: press *2767*3855# All data will be lost!
ClockWorkMod recovery Galaxy S 4G (in short: Vol UP + HOME + power ON Galaxy S 4G)
If not working, charge your battery fully before doing a hard reset! (and Backup :) )
PRESS AND HOLD VOLUME UP + Home Button (or VOLUME UP + DOWN)
Keep pressing these 2 buttons + press Power button for 2-3 Seconds
Release only power button, but KEEP pressing Volume up + Home Buttons (or VOL UP + DOWN)