How To Flash .nb0 Firmware or ROM via SUT-L3



Updated: June 26, 2024

Some stock ROMs and firmware packages come with the .nb0 file extension, which can't be flashed using common tools like SmartPhone Flashtool or Spreadtrum Update Tool.

While some device manufacturers allow .nb0 files to be flashed via the phone's stock recovery, this feature isn't universal. This guide will show you how to use the Software Update Tool (SUT) to flash .nb0 firmware files easily via your computer.


Before we begin, make sure you have the following:

  1. Your device's USB drivers - Find drivers here
  2. Software Update Tool (SUT) - Download SUT
  3. The .nb0 firmware file for your specific device
  4. A Windows PC
  5. USB cable
  6. Your Android device (ensure it's charged to at least 50%)

Step-by-Step Guide to Flash .nb0 Firmware

  1. Install Device Drivers

    • Download and install your device's USB drivers on your PC.
    • Restart your PC after installation to ensure the drivers are properly loaded.
  2. Set Up Software Update Tool

    • Download and install the Software Update Tool (SUT) on your computer.
    • Launch SUT-L3 after installation.
  3. Prepare the Firmware

    • Extract the downloaded .nb0 firmware from its zip archive.
    • Place the extracted .nb0 file in an easily accessible location (e.g., your desktop).
  4. Boot Device into Fastboot Mode

    • Power off your device.
    • Boot it into fastboot mode (also known as download mode or bootloader mode).
    • The method to enter this mode varies by device. It usually involves holding a combination of volume and power buttons while the device is off.
    • Alternatively, if you have ADB set up, you can use the command: adb reboot bootloader
  5. Connect Device to PC

    • Use a high-quality USB cable to connect your device to the computer.
  6. Load Firmware in SUT

    • In the SUT-L3 interface, click on the "..." button or the empty box.
    • Navigate to and select the extracted .nb0 firmware file.
    • Click "Next" to proceed.
  7. Configure Flashing Options

    • On the next screen, you'll see various options.
    • Select "Erase User Data" to perform a clean installation (recommended).
    • You may see other options like "Erase Cache" or "Format System" - select these if you want a completely fresh start.
  8. Start the Flashing Process

    • Click on the "Start" or "Flash" button to begin the firmware installation.
    • The flashing process will now commence. This may take several minutes.
    • Do not disconnect your device or interrupt the process to avoid bricking your device.
  9. Complete the Installation

    • Once the flashing process is complete, SUT will display a success message.
    • Safely disconnect your device from the PC.
    • Reboot your device manually if it doesn't do so automatically.
  10. Set Up Your Device

    • Your device will now boot into the newly flashed firmware.
    • Follow the on-screen instructions to set up your device.


  • If SUT fails to detect your device, try using a different USB port or cable.
  • Ensure your device is in the correct mode (fastboot/download) before starting the flash process.
  • If you encounter errors during flashing, double-check that you've downloaded the correct .nb0 file for your specific device model.
  • In case of persistent issues, try reinstalling the device drivers and SUT.

Wrapping up...

Flashing .nb0 firmware files using the Software Update Tool is a straightforward process when you follow these steps carefully. Always ensure you're using the correct firmware for your device to avoid potential issues. Remember, this process will erase all data on your device, so back up any important information before proceeding.

For device-specific instructions or if you encounter any difficulties, consult your device manufacturer's support resources or seek help from experienced users in Android development forums.