Here's my configuration on my S4:
Rom = Goldfinger v9
-- XXUGNK4, Thanks iB4STiD
Recovery = Safestrap 3.75
, Thanks Hashcode
Rooted = Towelroot
, Thanks geohot
for D/L link for Towelroot v3
Steps taken to unlock my AT&T Galaxy S4 I337 on NC1:
!!! POWERED DOWN MY S4 AND REMOVED MY AT&T SIM CARD THEN RESTARTED MY PHONE !!!
Skipped steps 1 -3, I did not downgrade to NB1, already rooted and safestrap installed.
Step 4 = Flashed MF3 Modules
Step 5 = Downloaded and installed RegionLock Away found in Post #1
, Thanks GalaxyMasterI337
. Clicked on Region Unlock, granted root, then rebooted when asked by RegionLock Away
Step 6 = When boot up completed, I went to dialer and Type *#0011# and waited for ServiceMode to pop up, Once it popped up I waited for 60 seconds and then removed the battery. I did not have a T-mobile sim card to test with so I just popped in my original AT&T sim card (!!! REMEMBER I TOOK IT OUT BEFORE I STARTED THE UNLOCK PROCESS !!!
) and powered on the phone. Phone booted up normal with no warnings or issues.
Step 7 = I re-flashed the NC1 Modules
, Thanks RockRatt
Step 8 = I went to two
T-Mobile stores to test out my phone with their sim card. I never got a warning as to "sim locked, enter sim unlock code or anything,"
I made a phone call and the other person answered and I also checked the APN settings and it listed T-Mobile as my network
Thanks and credit all goes to GalaxyMasterI337
for helping me to get my S4 Unlocked. I no longer have to wait until 12/2015 to get it unlocked by AT&T.