You have to note that there are several things that you have to do before rooting your device. If you cannot root your Android device successfully, you are able to troubleshoot the causes and then find out the correct solution such as downloading the latest version of KingoRoot, unlocking Bootloader and so on. Any changes cannot be made by users with the system with bootloader being locked so it will cause the rooting failure.

The manufacturer locks the Bootloader.

So, you have to try to download new version once it is released.

You download the KingoRoot version which is not the latest version.

The android version above 5.1 is not supported by KingoRoot.

There are some reasons why it can fail to root. It is not normal because usually the rooting process will take about 5 to 10 minutes. You see that completion is at 90%, then the rooting process is executed but it seems frozen. After 1 to 2 hours after you begin the rooting process, the completion percentage is stuck at 90. You may have downloaded KingoRoot via the mobile browser as an APK file and enabled USB debugging.

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