[wilnert]

samsung i747m version 4.1.2. from canada succesful unlock
1 need to root..using vroot
2 check new security
3 check skip Backuping MMCBLK

and click unlock..insert usb its done
no need to downgrade..

Selected model: I747M
Selected port: COM6 SAMSUNG Mobile USB Serial Port
Selected port speed: 115200
Searching ADB device... OK
Reading phone info...
Model: SGH-I747M
Android version: 4.1.2
Product code: SGH-I747RWBFMC
Phone version: I747MVLDMF1
PDA version: I747MVLDMF1
CSC version: I747MOYADMF1
IMEI: 353321052
Phone S/N: R21CB5SN9TK
Checking Super user right... true
Backuping MMCBLK... OK
Writing data to phone... OK
Rebooting phone... OK
Waiting phone... OK
Bypass MSL... OK
Unlocking... OK
Reseting... OK
Unlock done
Done with Samsung Tool v.17.6