Follow the steps to get free unlock for Samsung Galaxy S III and Samsung Galaxy Note II cell phone (for GSM version like AT&T, T-Mobile).
- First dial the following keys: *#197328640#
- Main Menu > [1] UMTS > [1] Debug Screen > [8] Phone Control > [6] Network Lock > Options [3]Perso SHA256 OFF > (wait for about 30 seconds)
- go back one step by pressing the Menu button then select Back, now you are in [6] Network Lock then choose [4] NW Lock NV Data INITIALLIZ ...
- Wait for a minute then reboot your phone. And your phone is unlocked!