UPDATE via WEB GUI
1. Go to [http://192.168.1.200/] or your specified IP address
2. Backup the current configuration by navigating to the Other Settings section in the main menu. Locate Config Operation at the bottom of the page, press the SAVE button, and save the JSON file
3. From the main menu, navigate to the File Systems section
4. Select Firmware and click the Upload file button
5. Upload the "mgb4-install_4.0.tgz" file
6. Create the "mgb4-flash" flag file by pressing the corresponding button
7. Optionally, create the "mgb4-keep" flag file by pressing the corresponding button to keep the current configuration after the update
8. Reboot the FG4 MultiBox by pressing the Reboot button
9. The FG4 MultiBox will boot into the flashing process

UPDATE via SD card (keeping configuration is not possible)
1. Power off the FG4 MultiBox
2. Copy the "mgb4-install_4.0.tgz" file to the SD card
3. Create the "mgb4-flash" file on the SD card (a blank text file with no extension)
4. Insert the SD card into the FG4 MultiBox
5. Power on the FG4 MultiBox
6. The FG4 MultiBox will boot into the flashing process
7. The FG4 MultiBox will power off automatically after flashing is complete
8. Remove the SD card before the next power-on

For more update options, see the user manual