CODES TO UNLOCK & LOCK SIM
If you want to be able to lock and unlock your SIM card without needing to dig through your phone settings for it, simply try the following codes:
#0111*0000000#: Use to unlock your SIM
#7465625*28746#: Use to turn on Auto SIM Lock
SAMSUNG CODES TO RESTART YOUR PHONE.
In order to restart your Galaxy phone without needing to hold down the power button, simply input either of the following USSD codes and watch the magic happen:
Dial #*3849#
Dial #*2562#
Dial #*3876#
Dial #*3851#