Galaxy S4 AT&T i337 New Security Easy Unlock 16.5

First Root Your Mobile With V-Root 1.7.2

Then

*#0808# dm+modem+adb Press ok *#9090# choice DM over UART .

connect usb cable and choose Samsung mobile usb serial port

Click on Repair And Tick Repair Efs\Baseband

Tick imei & Fill Your Samsung Original imei

Press Ok

100% Success

mobile is unlock

Br

Umesh Gaba