If you have the Samsung Galaxy Note 2 or even the Samsung Galaxy S3, you will be happy to hear that you can unlock your handset for free. When you have unlocked the device you can then use the device with any carrier or send it to a friend or family overseas.
For instance if you have bought the AT&T version of the Samsung Galaxy Note 2 then at the moment you are only able to use it with that carrier. But when you unlock it you can use it with any carrier.
So if you want to go ahead and unlock your device, follow the steps below.
Turn off the handset and insert a SIM card that is not your own, then turn the handset back on again.
Open up the dialpad and key in *#197328640#. Go to Main Menu >  UMTS >  Debug Screen >  Phone Control >  Network Lock > Options Perso SHA256 OFF > then wait for 30 seconds or so. Then hit Menus and choose Back. You should now see Network Lock. Then choose  NW Lock NV Data INITIALLIZ.
To make sure you didn’t make a mistake, the sequence you should have typed in is: Asterisk Pound One Nine Seven Three Two Eight Six Four Zero Pound. However some people call the asterisk the star button and the pound button is sometimes called hash.
The device should now be unlocked and you should be able to use it anywhere in the world. You might want to try using the same code with other devices as it has been used for some time.