Android has something called the root user account, but it’s tucked away so nobody can touch it until they choose to unlock it. Android feels it is best that way so everyone can use the operating system as safely as possible and anyone who is savvy enough to know what root access even is can unlock it when they choose to do so. Having the Android operating system rooted is necessary for developers, but it is also a requirement if you want to use any of the thousands of additional apps that are available from the Google Play Store and other websites online. These apps can do great things but before they can do anything they need to have the power over the operating system to do so. With Android and the Linux kernel, in particular, we call this root access or access to the root user account.
- You need to have the Samsung Galaxy A3 smartphone that comes with the SM-A310N0 model number before you can flash the rooting file found in this guide. Flashing the wrong file of CF-Auto-Root often means the device is bricked until you flash the right stock ROM on the device.
- You must have a computer that is running on a version of the Windows operating system to use this guide. The Odin flashing tool developed by Samsung was created to work with Windows operating systems only.
BEFORE WE BEGIN
- Note that Chainfire had the MMB29K.A310N0KOU1BPFA firmware build number running on the Samsung Galaxy A3 smartphone before he created the rooting tool found in this guide. It does not mean you need to be running the same firmware version on your Samsung Galaxy A3 smartphone before using this guide. You just need to have the fight model number (SM-A310N0) and to be running on the Android 6.0.1 Marshmallow software update, and the rooting should work for you.
- You need to install the Samsung USB Drivers  on the Windows operating system that is running on your computer that you plan on using in this guide if the computer doesn’t have the Samsung USB Drivers installed on it already. Those drivers are what makes your smartphone connect to the flashing application running on the computer and without them the rooting does not work.
- You need to have unlocked the Developer Options menu  on the Samsung Galaxy A3 smartphone if you are going to have able to make changes to the Android software that then allows for the rooting to happen. The only way to allow that to happen is by enabling the USB Debugging Mode  that is an option for you to turn on from within the Developer Options menu.
HOW TO ROOT SAMSUNG GALAXY A3 SM-A310N0 RUNNING ANDROID 6.0.1 MARSHMALLOW USING THE CF-AUTO-ROOT TOOL BY CHAINFIRE
- Download the CF-Auto-Root  tool for the Samsung Galaxy A3 SM-A310N0 running Android 6.0.1 Marshmallow.
- Open the Downloads folder and extract the CF-Auto-Root file that is there to the same Downloads folder location and you get the Odin flashing application and the flashable rooting file available.
- Run the Odin flashing application so that it is open when you connect the device to the computer in the following step.
- Boot the Samsung Galaxy A3 SM-A310N0 smartphone into the Download Mode  and connect it to the computer with the USB cable that is available out of the box for the battery charging.
- Doing so should result in the ID: COM port in Odin lighting up with a yellow r blue color and the added message appear from the Log entry area if the Samsung USB Drivers are installed correctly (See the before we begin section).
- Click the AP button and then browse through to the Downloads folder where you extracted the rooting file in the beginning and select the MD54 rooting file to upload to the AP location in Odin.
- Click the Start button and the rooting begins.
- Since this is the CF-Auto-Root tool based on the Android 6.0.1 Marshmallow it no longer goes through the system partition to root the device and is what is called a systemless root for that reason. The rooting process also differs in the sense that it can take a few minutes longer and boot loop a few times. These are not things to worry about this time.
- Wait until the green pass box shows up in Odin before unplugging from the computer.
In conclusion, that is how to root Samsung Galaxy A3 SM-A310N0 smartphone running on the Android 6.0.1 Marshmallow software updates by flashing the systemless root version of the CF-Auto-Root tool that no longer requires you to download the stock ROM or visit the SuperSU app to unroot. Instead, you can get it done by taking the hard reset from the recovery Mode.