How to Unlock a Samsung Phone From AT&Tby W. Nicole Barclay
Unlocking your Samsung cell phone will enable it to be used outside of the AT&T service. Not only will it function with the AT&T service, but with any other carrier and any other SIM card, anywhere in the world.
Power phone off. Remove AT&T SIM card and insert any other SIM card from any other carrier. Power phone on.
Wait to be prompted for a "Password." Enter unlock code.
Note that if your phone says "Insert correct SIM card" your method is slightly different. Enter #0111* followed by your unlock code and the # sign.
Select "OK" if prompted to confirm. Restart phone to confirm unlocking.