Blocking Xiaomi bootloader on MIUI 14 without data loss: full guide

The bootloader on Xiaomi smartphones is a software component that runs to the operating system and determines which software will be downloaded, and is blocked by default on all devices of the brand, but many users will unlock it to install custom firmware, obtain root rights or test beta versions of MIUI. However, after experiments, it is often necessary to return everything “as it was” – especially before selling the phone, contacting a service center or to restore warranty.

In this article, we will discuss how to block a Xiaomi bootloader with MIUI 14 without losing data – that is, saving photos, applications, settings and files. The process requires care, as improper actions can lead to a “brick” (complete failure) of the device. We will consider official and alternative methods, their pros and cons, and give recommendations for preparation.

Important: The procedure is suitable for most MIUI 14-based Redmi, Poco and Mi models (including Xiaomi 13/13 Pro, Redmi Note 12, Poco F5, etc.), but may differ for MediaTek processors (unlike Qualcomm Snapdragon).

Why do I need to block the bootloader and what are the risks?

An unlocked bootloader gives the user freedom, but creates vulnerabilities:

• 🔓 Security: The device becomes vulnerable to malware that can modify system files.
• 📱 Guarantee: Most Xiaomi service centers refuse warranty repairs when unlocked bootloader is detected.
• 🔄 Updates: Some OTA-update MIUI They may not be installed or work properly.
• 💰 Resale: Buyers often check the status of the bootloader before buying a used smartphone.

However, locking the bootloader is not just a “reverse process” of unlocking.

• 🚨 Data loss: If wrong actions, the phone may require a factory reset.
• 🔧 Device Brick: Incompatible firmware or interrupted process will lead to “bricking».
• ⚠️ Loss of loss IMEI: On some models (for example, Redmi Note 10 Pro) the lock can reset network settings.

⚠️ Note: If you have installed custom recavers (for example, TWRP) or modified system partitions (e.g, /system or /vendor), Before you lock the bootloader, you have to put them back in the stock state, otherwise the phone won't boot!

Preparation of the device: what to do before blocking

Before starting the procedure, follow the mandatory steps:

Backup your data via Mi Cloud or locally

Check the MIUI version (must be at least 14.0.1)

Make sure the battery is at least 60% charged

Download the official firmware for your model from the Xiaomi website

Disable Mi Account protection (if enabled)

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Pay special attention to backup, and even if the process is successful, some applications (e.g. banking) may require re-authorization.

• ☁️ Mi Cloud: Sync contacts, notes, photos and SMS (In Settings → Xiaomi Account → Mi Cloud).
• 📱 Local Copy: For applications and their data, use Swift Backup or Titanium Backup (requires root).
• 💾 Copy of section EFS: If you have modified your phone, save the folder. /efs — contains IMEI and network settings.

Also check the status of the bootloader.

1. Turn off the phone.
2. Press Volume Down + Power to enter Fastboot.
3. Connect the device to your PC and type the command: fastboot oem device-info If the answer has the line Device unlocked: true, the bootloader is unlocked.

⚠️ Note: Some models (e.g. Xiaomi) 12T) After blocking the bootloader, the Widevine settings are reset. L1, Which leads to loss of support HD Netflix and Disney+. Before the procedure, check the status of Widevine in the application. DRM Info.

The official method: lock through Mi Unlock Tool

Xiaomi provides the official Mi Unlock Tool, which can be used to lock the bootloader, but this method requires linking the Mi Account to the device and waiting 72 hours (unless the account was previously linked).

Step-by-step:

1. Download Mi Unlock Tool from the official website (version must be at least 5.5.224.30).
2. Sign in to Mi Account on your phone and PC (should be the same account!).
3. Turn on USB debugging: Go to Settings → About Phone. Tap 7 times on MIUI to activate Developer Mode. Go back to Settings → Additional → For Developers and turn on USB Debugging.

Connect your phone to your PC

Fastboot

Loudness down + Nutrition

Launch the Mi Unlock Tool

Lock

It takes 5-10 minutes. When the phone is finished, it automatically restarts. If the device is stuck on the MIUI logo after locking, reset via Recovery (click Volume Up + Power and select Wipe Data).

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If the Mi Unlock Tool is running a "Couldn't unlock" error, try using an older version of the utility (e.g. 3.5.1128.45) and download it from the 4PDA or XDA Developers forums.

Alternative method: blocking through fastboot commands

If the official tool doesn’t work (for example, due to a Xiaomi server error), you can lock the bootloader manually via fastboot. ADB/Fastboot and the official firmware for your model.

Instructions:

1. Download the firmware for your device from MIUI Downloads. Choose the version of Fastboot (file with the extension.tgz or.zip).
2. Unpack the firmware in a folder on your PC. flash_all_lock.bat (for Windows or flash_all_lock.sh (for Linux/Mac).
3. Connect your phone in Fastboot mode and launch the script: flash_all_lock.bat Nana Mac/Linux Use the command: chmod +x flash_all_lock.sh./flash_all_lock.sh

Decisions:

1. Check the firmware: Download the correct version MIUI For your model (for example, for Xiaomi) 13 Global needs firmware marked ingres. Repeat the firmware through fastboot using script flash_all_except_storage.bat (retain).

Restore the IMEI

Contact the service.

EDL-regime

Xiaomi

If you're not sure what you're doing, you should go to a specialist, and self-recovery efforts can make the problem worse.

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Before blocking the bootloader, always check the firmware compatibility with your model. For example, the firmware for the Redmi Note 12 Global (sweet code) will not work for the Redmi Note 12 Pro+ version.

How to check if the bootloader is successfully blocked?

After the procedure is completed, you need to make sure that the loader is actually locked.

1. Turn off the phone.
2. Press Volume Down + Power to enter Fastboot.
3. Connect the device to your PC and execute the command: fastboot oem device-info The answer should be: Device unlocked: false

FAQ: Answers to Frequent Questions