Basic requirements

  1. Make sure your computer has working adb and fastboot. Setup instructions can be found here.
  2. Enable USB debugging on your device.

Unlocking the bootloader

  1. Enable OEM unlock in the Developer options under device Settings, if present.
  2. Accept the terms that you understand that you’re voiding your warranty by choosing to unlock your bootloader.
  3. Login with your Lenovo account (if you already have one) or create a new one.
  4. A 14 days countdown timer will start. This is specific per device.
  5. After the waiting period, go back to OEM unlocking so that the Lenovo servers can toggle the bootloader unlock switch.

  6. Connect the device to your PC via USB.
  7. On the computer, open a command prompt (on Windows) or terminal (on Linux or macOS) window, and type:

     adb reboot bootloader
    

    You can also boot into fastboot mode via a key combination:

    • With the device powered off, hold Volume Down + Power.
  8. Once the device is in fastboot mode, verify your PC finds it by typing:

     fastboot devices
    
  9. Now type the following command to unlock the bootloader:

     fastboot oem unlock
    
  10. If the device doesn’t automatically reboot, reboot it. It should now be unlocked.
  11. Since the device resets completely, you will need to re-enable USB debugging to continue.

Installing a custom recovery using fastboot

  1. Download a custom recovery - you can download TWRP.

  2. Connect your device to your PC via USB.
  3. On the computer, open a command prompt (on Windows) or terminal (on Linux or macOS) window, and type:

     adb reboot bootloader
    

    You can also boot into fastboot mode via a key combination:

    • With the device powered off, hold Volume Down + Power.
  4. Once the device is in fastboot mode, verify your PC finds it by typing:

     fastboot devices
    
  5. Flash recovery onto your device:

     fastboot flash recovery twrp-x.x.x-x-kuntao.img
    
  6. Now reboot into recovery to verify the installation:
    • With the device powered off, hold Volume Up + Volume Down + Power.

Installing LineageOS from recovery

  1. Download the LineageOS install package that you’d like to install or build the package yourself.

    • Optionally, download 3rd party application packages such as Google Apps (use the arm64 architecture)
  2. Place the LineageOS .zip package, as well as any other .zip packages on the root of /sdcard:
    • Using adb: adb push filename.zip /sdcard/
    • You can use any method you are comfortable with. adb is universal across all devices, and works both in Android and recovery mode, providing USB debugging is enabled.
  3. If you aren’t already in recovery, reboot into recovery:
    • With the device powered off, hold Volume Up + Volume Down + Power.
  4. (Optional, but recommended): Select the Backup button to create a backup.
  5. Select Wipe and then Advanced Wipe.
  6. Select Cache, System and Data partitions to be wiped and then Swipe to Wipe.
  7. Go back to return to main menu, then select Install.
  8. Navigate to /sdcard, and select the LineageOS .zip package.
  9. Follow the on-screen prompts to install the package.
  10. (Optional): Install any additional packages using the same method.
  11. (Optional): Root the device by installing the LineageOS su add-on (use the arm64 package) or using any other method you prefer.
  12. Once installation has finished, return to the main menu, select Reboot, and then System.

Get assistance

If you have any questions or get stuck on any of the steps, feel free to ask on our subreddit or in #LineageOS on freenode.