If you are looking for a way to unlock the older Samsung Galaxy Note smartphones, the leaked unlock code might help you do just that. It is said that the unlocked code for the Samsung Galaxy Note 3 was leaked by a Samsung insider. Here is how to use it to unlock your smartphone.
Start by fitting in a new SIM card. Once that is done, restart the device and open up the dial pad. Key in the code *#197328640#. Next, choose UMTS >  Debug Screen >  Phone Control >  Network Lock > Options  Perso SHA256 OFF.
You will have to wait for 30 seconds or more before pressing Back to enter the Main Menu once more. Now, select  NW Lock NV Data INITIALLIZ. Your Samsung device should be unlocked now.
It is said that the code also works on the older Samsung Galaxy Note 2 as well so you might want to give that a try as well.