Unlocking the bootloader Xiaomi Redmi 4X: the official way without errors

Introduction: Why unlock the bootloader on Redmi 4X

Xiaomi Redmi 4X (codenamed santoni) is still popular among Android customization enthusiasts, with the main obstacle to installing custom firmware, root rights or alternative recoveries being a blocked bootloader, which restricts access to system partitions to protect the device from unauthorized changes and potential security threats.

Unlocking the bootloader opens up opportunities for deep customization of the smartphone, from installing TWRP and LineageOS to optimizing performance through the FrancoKernel or ElementalX cores. However, the process comes with risks - from loss of warranty to a full "brick" (turning the phone into a "brick"). In this article, we will discuss the official method of unlocking through the Mi Unlock Tool, as well as alternative ways for experienced users.

Important: The procedure is relevant for all versions of the Redmi 4X, including modifications with 2/16 GB, 3/32 GB and 4/64 GB of memory. But before you start, check if your device is not included in the list of exceptions (for example, models for the Chinese market with reference to Mi Account).

Preparation for Unblocking: Requirements and Warnings

Before proceeding, make sure all conditions are met:

  • 📱 Device: Xiaomi Redmi 4X (Check the model in Settings → The phone. → Model).
  • 🔄 Version. MIUI: Global Stable 8.5.1.0 (older versions may require an update).
  • 🔐 Mi Account: Linked to the device, confirmed by SMS/email, without restrictions (e.g. blocking for suspicious activity).
  • 💻 PC: Windows 7/10/11 (64-bit), Administrator rights and disabled Windows Defender.
  • 🔌 Cable: original USB Type-C (Poor cables can cause a Couldn't unlock error).

Critical points that are often overlooked:

⚠️ Attention: If your Redmi is 4X It was purchased in China (market version) CN), Unblocking is possible only through the Chinese account Mi with reference to the number +86 Current account is different from the account info on the device.

Please note that after the unblocking:

  • 🔒 All data (including photos, contacts and apps) will be dumped).
  • 🛡️ Find Device and Mi Cloud will be disabled before re-binding.
  • ⚠️ Xiaomi warranty is cancelled (even if the bootloader is later blocked back).
📊 You have already tried to unlock the bootloader on Xiaomi?
Yes, successfully.
Yeah, but there were mistakes.
No, it's my first time.
I'm planning on trying.

Step 1: Linking your Mi Account to your device

The most common reason for unlock errors is the incorrect account binding. Xiaomi requires that the device be “authorized” in the system for at least 72 hours (3 days) before unlocking.

  1. Go to Settings → Mi Account and log in (or create a new account).
  2. Enable data synchronization: Settings → Mi Account → Synchronization.
  3. Activate the Settings option → Additional → For developers → Mi Unlock status (if there is no item, first turn on the developer mode).
  4. Connect your device to the Internet via mobile data (Wi-Fi may not work!) and wait for the notification: Added successfully. Bound in XX hours.

Important: Do not log out, do not reset your phone or change your account SIM-card for 72 hours, and avoid using it. VPN Xiaomi blocks accounts if it suspects a change in geolocation.

What to do if the time of fixation does not decrease?
If the timer in Mi Unlock Status is stuck for "72 hours", try: 1. Reboot the phone. 2. Disable / turn on mobile data. 3. Delete and re-add Mi Account (only if less than 10 minutes have passed since the first link!). 4. Use another account (if the first one was blocked for frequent attempts).

Once you've successfully linked, you'll see a message saying, This device is bound to your Mi Account. Now you can move on to the next step.

Step 2: Install Mi Unlock Tool and Drivers

The official unlock tool, the Mi Unlock Tool, is only available for Windows. Download it from Xiaomi's official website (version no lower than 5.5.224.24). Avoid third-party sources - they may contain viruses or outdated builds.

Installation algorithm:

  1. Unpack the archive from the Mi Unlock Tool into a folder without Cyrillic characters (e.g., C:\MiUnlock).
  2. Launch it. miflash_unlock.exe on behalf of the administrator.
  3. Accept the license terms and log in to the same Mi Account that is linked to the phone.
  4. Install drivers manually (unless Windows finds them automatically): 🖥️ Open Device Manager (Win) + X → Device Manager). 🔌 Connect Redmi off. 4X To the PC, keeping Volume down + Power (Fastboot mode). 🔍 The controller will have an Android device with a yellow exclamation point. Update the driver by specifying the folder with the Mi Unlock Tool.

If Windows is blocking the installation, turn off driver signature verification:

  1. Press Win + R, enter shutdown /r /o /f /t 0.
  2. After rebooting, select Diagnostic → Additional settings → Download options → Reboot.
  3. Press F7 (disable mandatory signature verification).

Mi Account is tied to 72+ hours |Mi Unlock Tool version 5.5.224.24 or later | Drivers installed (no errors in Device Manager) | Original USB Cable (checked for data transfer) | Antivirus and Windows Defender disabled

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Step 3: Unlock process with Mi Unlock Tool

When everything is ready, follow the instructions:

  1. Turn off the Redmi 4X and put it into Fastboot mode: Press Volume Down + Power for 10 seconds. The screen should show the hare in the eardress cap (Fastboot logo).
  2. Connect your phone to your PC. In Mi Unlock Tool, press Unlock.
  3. Wait for the device to be checked (it can take up to 5 minutes). If a Couldn't unlock error appears, see the solutions section.
  4. Once successfully unlocked, the phone will automatically restart. The first boot will take up to 10 minutes - don't interrupt the process!

Instructions:

  1. Turn the phone into EDL mode: turn off, press Volume up + Volume down + Power for 10 seconds (the screen will remain black).
  2. Device Manager should appear Qualcomm HS-USB QDLoader 9008.
  3. Flush the firmware through Mi Flash Pro by selecting the Clean all and lock option (this will unlock the bootloader).

⚠️ Attention: Use EDL-mode on anti-rollback devices (for example, after updating to the MIUI 12+) Check the anti-rollback version with the fastboot getvar anti command before starting.

Method 2: Exploitation through ADB (for older versions of MIUI)

There was a bug on MIUI 8-9 firmware that allowed you to unlock the bootloader without waiting 72 hours.

  1. Turn on USB debugging and connect your phone to your PC.
  2. Follow the commands: adb shell su setprop persist.service.adb.enable 1 setprop persist.security.adbinput.disable 0 exit exit
  3. Reboot to Fastboot and try unlocking through the Mi Unlock Tool.

On newer versions of MIUI, this method does not work.

FAQ: Frequent questions about unlocking Redmi 4X

Can I unlock the bootloader without losing data?
No. Unlocking through the Mi Unlock Tool will necessarily result in factory resets. The only way to save data is to back up through TWRP, but you already need an unlocked bootloader to install it, so you get a vicious circle, and we recommend you copy important files to your PC or cloud in advance, and sync your contacts with your Google Account.
How to check if the bootloader is unlocked on Redmi 4X?
There are three ways: Turn off your phone and turn it on, holding Volume down + Power. If the bottom of the screen says Unlocked, the bootloader is unlocked. Type in the PC terminal command: fastboot oem device-info Look for Device unlocked: true. Install the Bootloader Checker app from Google Play (only works on some firmware).
What if the phone doesn’t turn on after unlocking?
There was probably a mistake when resetting the data. Try: Load to Fastboot. + Power) and execute: fastboot erase userdata fastboot reboot If it doesn't work, run the firmware through the Mi Flash Tool in Clean all mode. EDL-If the screen is black, check if the eMMC chip is burned (typical for memory-worn devices).
Can I lock the bootloader back?
Yes, but it's not safe. To lock: Sweep through the official firmware through the Mi Flash Tool with the Clean all and lock option. Or follow the command: fastboot oem lock.
Does unlocking on Redmi 4X work with Snapdragon 435 processor?
Yes, all Redmi 4X modifications (including versions with Snapdragon 435 and 2/3/4 GB of RAM) support unlocking via Mi Unlock Tool. Except for devices with locked EDL (for example, after repairs under warranty in unofficial services). To check the processor model, type in the terminal: adb shell cat /proc/cpuinfo Look for Hardware: Qualcomm Technologies, Inc MSM8940 (this is Snapdragon 435).

How to Enable Developer Mode on Redmi 4X

Without activating the developer mode, you can't enable OEM Unlock and USB Debugging. Here's how to do it:

  1. Go to Settings. → The phone.
  2. Find the MIUI version and tap it 7 times in a row (you should be notified you became a developer!).
  3. Return to the main settings – there will be a new section for developers.
  4. Activate options: 🔧 Debugging by USB (Allow access when connecting to the PC). 🔓 Unlocking OEM (It may be hidden – see below).

If there is no OEM Unlocking:

  • Update MIUI to the latest version.
  • Try resetting (Settings → Additional → Restore and Reset).
  • Use alternative methods of unlocking.

Note: On some Redmi 4X firmware, the OEM Unlock option only appears when the Mi Account is linked to the device.