: Go to Settings > About Phone and tap the Build Number (or MIUI version for Xiaomi) 7 times.

Huawei discontinued official bootloader unlocking, but for legacy devices:

Several scenarios can lead to this error:

In most regions, yes. Manufacturers consider unlocking the bootloader as a warranty-voiding action, though some (like OnePlus and Google) allow it with caveats.

Remove paper trays, look for stuck paper behind the fuser or near duplexer. Even a small scrap can hold a lock flag.

This long-form article will dissect every component of this error, explain why it occurs, and provide step-by-step solutions to unlock the "lock flag" and successfully flash your device.

Inside your device's storage chip, there is a dedicated controller. This controller manages how data is written, read, and erased. It does not simply accept commands blindly; it checks a specific configuration file or register known as the Flash Configuration (FC) or Device Configuration (DC) .