Once you have successfully unlocked the bootloader, the “check” behaves differently:

On some MIUI/HyperOS versions for REDMI Note 12 4G:

If response includes ERROR: Command not allowed → bootloader locked. If returns a hex value → unlocked.

Before you attempt any modification, you need to know whether your bootloader is (default state) or Unlocked .

The easiest way to check the bootloader status on your Redmi Note 12 4G does not require a computer. However, this method is sometimes hidden or misleading depending on your current MIUI version. Here is how to find it.

For the majority of users, keeping the bootloader locked is the safest option. But for enthusiasts who want to extend the life of their Topaz/Tapas with Android 14/15 custom ROMs (long after Xiaomi stops updates), passing the bootloader check via the official Mi Unlock process is the only legitimate path.

Two reliable methods exist: (low-level) and ADB/Developer options (high-level). Method 1 is definitive.

When the bootloader check fails, you get cryptic error codes. Here is what they mean and how to fix them.

: An unlocked bootloader is required to install custom ROMs or root your device. officially unlock the bootloader if it is currently locked? How to check bootloader REDMI Note 12 4G? - HardReset.info