Samsung Unlock Code by IMEI

1. Turn off your Samsung phone
2. Insert a sim card from a new carrier (different from the original carrier). 
3. Turn on the phone.
4. Unlock the screen by sliding across the screen or by entering your screen PIN number.
5. The phone will prompt automatically for a SIM NETWORK UNLOCK PIN
6. Enter the Network unlock code (also called NCK) that you obtained from UnlockMySim.com
7. Your phone is now fully unlocked!

If you get the response. UNSUCCESSFUL or BLOCKED then proceed to the next steps.

If it Says Unlock Unsuccessful or  PUK Blocked:

1. Turn off your Samsung phone
2. Insert a SIM card from a new carrier (different from the original carrier). 
3. When prompted for the SIM NETWORK UNLOCK PIN (Network code) type the DEFREEZE code provided (also referred to as MCK).  You will receive an unsuccessful message, don’t worry.
4. Your phone will again prompt for a SIM NETWORK UNLOCK PIN, on the seconds attempt enter in your NETWORK CODE (NCK) that we provided.
5. It will says Successful
6. Your phone is now fully unlocked!

If you get “unsuccessful” again then hit Dismiss button and type *2767*3855# on phone keypad  to factory reset your phone and restore all settings (warning: all your personalized info and pictures will be lost unless you back up your phone first).  Once the phone has been reset, enter the Defreeze code on the first attempt when prompted, and enter the Network code on the second attempt when prompted.