Links to needed
files
Download the files
linked below
Odin3_V3.09 downloader link
USB Driver Link
Grab the original
T999UVUEMJC stock firmware:
CF-Auto-Root for
Galaxy S3 (T-Mobile) SGH-T999
Power off phone
Boot phone to
download mode
Use Odin 3 to
install 4.3 stock ROM
Phone will reboot
when complete
After 1st boot power
off phone
Boot phone back in
to download mode
Use Odin to install
CF-Auto-Root
Phone will reboot
when complete
When Phone is back
up and running after 1st boot
Enable SuperSU in
Settings/More/Application Manager
Go to Google Play
Apply update for
SuperSU
If not showing up,
Install from Google Play
Open up SuperSU
Allow app to
update/Allow app to disable KNOX
Wait patiently for a
few minutes
Reboot device
You now have root
