The error means you are attempting to flash custom firmware, a custom recovery, or an operating system image via Android Open Source Project (AOSP) Fastboot while your device's bootloader security flag is active. The "remote" error code indicates that the connected device's hardware safely rejected the command to protect against bricking or unauthorized data extraction.
On your computer, download the latest Platform Tools from Google's official source. Extract the ZIP file to an easily accessible folder, such as C:\platform-tools on Windows or /Users/[YourName]/platform-tools on macOS/Linux.
If you are seeing this error pop up in your command-line interface—whether you are using fastboot , trying to install a custom ROM, or unbricking a device—you have come to the right place.
: Open your device's primary Settings app, choose About Phone , and locate the Build Number . Tap this entry rapidly 7 times until an on-screen notification confirms that Developer Options are unlocked. The error means you are attempting to flash
Prevention is always better than cure.
For Unisoc (SPD) devices, simply unlocking the bootloader is not always enough. The device checks an AVB (Android Verified Boot) vbmeta partition for a flag. A proven fix used by developers is to:
sudo flashrom -p internal --wp-disable sudo flashrom -p internal --wp-range 0 0 Extract the ZIP file to an easily accessible
or flashing generic GSI system images onto Unisoc/Spreadtrum or MediaTek platforms. Why Fastboot Rejects Your Flashing Command
: The physical state of the bootloader chip. If the flag reads LOCKED , the processor rejects arbitrary write instructions via Fastboot, prompting the remote failure syntax. Step-by-Step Resolution Guide
The "Failed -Remote 39:Flashing Lock Flag is Locked. Please Unlock it First" error typically arises due to security features implemented in the device's firmware. Manufacturers often include mechanisms to prevent unauthorized or accidental flashing of firmware, which could potentially brick the device or cause it to malfunction. The flashing lock flag is one such mechanism that locks the device, preventing any flash operations until it is explicitly unlocked. Tap this entry rapidly 7 times until an
Locate the toggle switch and flick it to the ON position. Enter your lock screen PIN or password to authorize this action.
Submit the ID on the to receive a unique unlock key. What to Do After Unlocking
To understand why this error occurs, one must understand the architecture of modern embedded flash memory (eMMC or UFS).