These are the steps to root Samsung Galaxy Grand 2 LTE SM-G7105H smartphones running on the Android 4.4.2 KitKat software update. The guide will install and enable SuperSU on your device — the same SuperSU that is developed by Chainfire who also makes the CF-Auto-Root tool in this guide. Chainfire is a talented developer who has also gone on to make other useful programs, including the Triangle Away app you can install on your Samsung device.
- The CF-Auto-Root package for the Samsung Galaxy Grand 2 smartphone in this guide is based on firmware with the KOT49H.G7105HWAUBNK3 build ID. That same build ID is part of an Android 4.4.2 KitKat software update that was rolled out to some regions. It does not mean you have to get up and flash that same firmware on your Samsung Galaxy Grand 2 smartphone before using this guide. The guide should work on all versions of Android 4.4.2 KitKat.
- You must have the Samsung Galaxy Grand 2 LTE smartphone with the model number SM-G7105H to use this guide. Any other model number will probably get bricked during this guide.
BEFORE WE BEGIN
- Download the Samsung USB Drivers  for the Samsung Galaxy Grand 2 LTE device and install them on your computer running Windows before you start with the guide.
- Unlock the Developer Options menu if you cannot see it from the Settings on the Grand 2 device by tapping on the Menu > Settings > About Device > Build Number.
- Enable the USB Debugging Mode on the Grand 2 smartphone by tapping on the Menu > Settings > Developer Options > USB Debugging Mode.
HOW TO ROOT SAMSUNG GALAXY GRAND 2 LTE SM-G7105H RUNNING ANDROID 4.4.2
- Download the CF-Auto-Root package for the G7105H on Android 4.4.2 from this link .
- Download the Odin flashing tool from this link .
- Extract the files on the desktop of your Windows computer.
- Boot the Samsung Galaxy Grand 2 smartphone in download mode and connect it to the computer with the USB cable.
- Click the PDA or the AP button and browse the desktop for the CF-Auto-Root tar.md5 file for the Grand 2 smartphone.
- Do not many any changes to the default settings you get from the Odin flashing tool’s user-interface.
- Click the Start button and the Odin app will now flash Chainfire’s CF-Auto-Root exploit on your Grand 2 smartphone, installing and enabling SuperSU.
- For everything to go smoothly, the Samsung Galaxy Grand 2 smartphone must reboot in recovery mode — it will do this automatically.
Any Samsung Galaxy Grand 2 smartphone that does not get in recovery mode must force it in recovery manually by using the appropriate hardware key combination for that mode. You can get your Samsung Galaxy Grand 2 device in the recovery mode you need by holding the Volume Up + Home + Power buttons during the booting phase.
Did you just update OTA or flash a firmware file through Odin? Often people choose to root directly after OTA updates, but that is the most dangerous time to root. New software updates can bring in new bootloaders that can cause a device to not boot. When that happens people need to report it to Chainfire so he can then fix the problem. You can report any problems to Chainfire directly by replying to the official CF-Auto-Root thread  at XDA Developers.