[AT&T Galaxy Note 3 Q&A, Help & Troubleshooting] a82320:
I bought many unlock code for ATT NOTE 3 from one of my trusted site, which unlocked many of my NOTE 3s and iPhones in the past months.

However, this time, the situation is I got the code from the them, followed same precedure, entered unlock code, and the phone just showing "network unlock unsuccessful" .

the phone is brand new bought from ATT store, and double checked IMEI, which matches box, phone, and *#06#'s IMEI. so the IMEI is correct, the website checked the unlock code is correct also.

but I just can't get my phone to unlock this time, always showing "network unlock unsuccessful" with the correct unlock code. anyone has any clue and why?

PS:have tried following method, NONE of them worked, either not working method or can't find UMTS option in my note 3.

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Solution #1

(Samsung Galaxy S2, S3, Note , Note 2)

Follow these step carefully, as long as you have the correct code it will work 100% (Your phone must be updated to the latest firmware!)

1. Please trouble shoot as usual with the customer, the code must be correct and the phone MUST prompt for the code.

2. If nothing we can proceed to use the "release method" on the phone(s):

a. Go to the Dial pad and dial *#197328640#

b. Please click on number [1] UMTS > [1] Debugging screen > [8] Phone Control > [6] NETWORK LOCK

c. You will see 3 options

d. Please click on number [1] Perso Sha256 INFO, the screen will change slightly

e. Please hit the MENU button then when the menu pops up please carefully hit BACK to return to the previous screen

f. Please click on number [2] Perso Sha256 ON, the screen will change again to a one line message

g. Restart the phone on the screen by holding the power button and click RESTART

h. When the phone prompts for the unlock code simply enter the unlock code

i. Your phone is now permanently unlocked!

(Samsung Galaxy S4 Only)

Follow these step carefully, as long as you have the correct code it will work 100% (Your phone must be updated to the latest firmware!)

1. Make sure that the phone PROMPTS for the code with a NON accepted sim card and that your IMEI is correct by dialing *#06#

a. Go to the Dial pad and dial *#0011#

b. Please click your MENU button (Bottom LEFT button) and click BACK on the menu that appears, Nothing will happen do not worry please move to the next step

c. Please click your MENU button AGAIN and this time click KEY INPUT

d. When the Key input box appears please input the number "1" and hit OK

e. You will see a number 1 for a while, please wait until it changes into the SERVICE MENU

f. Please click [1] UMTS > [1] DEBUGGING SCREEN > [6] Phone Control > [6] Network LOCK

g. You will see 3 OPTIONS within Network LOCK

h. Please click on number [1] Perso Sha256 INFO, the screen will change slightly

i. Please hit the MENU button then when the menu pops up please carefully hit BACK to return to the previous screen

j. Next Please click on number [2] Perso Sha256 ON, the screen will change again to a one line message

NOTE: If you see ENABLE_FLAG[1], refer to the notes below. If you see ENABLE_FLAG[0], proceed with step k.

k. Restart the phone on the screen by holding the power button and click RESTART

l. When the phone prompts for the unlock code simply enter the unlock code provided to you

m. Your phone is now permanently unlocked!

*If this is not working, go to Solution #2

*NOTE - If it shows ENABLE_FLAG[1]:

Press menu, select back to go back to the Network Lock menu.

Select [3] Perso Sha256 OFF, then select the first item after.

It will say "Menu not exist".

Press menu, select back, press menu, select back to go back to the network lock menu again.

Select [2] Perso Sha256 ON again

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