Use kingroot, then download rashr from the Play store, get twrp for galaxy light then flash using rashr, next get supersu zip then reboot to recovery and install, worked for me.
1) install supersu from teh market
2) flash rooted kernel in odin
3) boot up and enable usb debugging
4) run the rooting batch script to root your phone
5) flash stock kenrle back to get wifi etc back
6) enjoy root.
i need someone to then run this command in adb shell or teminal emulator
adb shell
su
dd if=/dev/block/platform/dw_mmc.0/by-name/RECOVERY of=/sdcard/stock-t399-recovery.img
So much misinformation being spread around, a locked bootloader only blocks the install of custom images, not root. should you guys have a locked bootloader youll be the first locked samsung device on tmobile, the only way youll know is when someone flashes a custom kernel.
source code helps you with nothing as i said :/, odin images come from either kies or are leaked i would suggest reaching out to samfirmware.com instead as samsung will ignore you. motochopper would never work on this as it has an exynos cpu and motochopper is for qualcomm. so exploits more like exynos abuse or framaroot are ones you should look at but i doubt any of them will work.
flashing modded images via odin will work, however youve no way to make them without teh stock files, you cant dump them without using dd (which needs root). its a rather vicious cycle, but once you get root and get cwm you are set for life :/
For what it's worth to the other developers I got Alex from androidfilehost.com to add this device so if you wanna upload stuff you can now do it there
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