Message “This device is locked” on Xiaomi Mi 7: reasons and all ways to unlock

You turned on the Xiaomi Mi 7 (or another Mi/A1/Redmi series based on Qualcomm Snapdragon), but instead of the usual boot system saw a black screen with the inscription “This device is locked” and the Mi logo? This means that the device is activated bootloader lock, and the system can not continue to launch.

In this article, we will discuss in detail why a message appears (including after a reset, firmware or update), how to officially unlock the bootloader through Xiaomi tools, alternative methods (including bypassing the lock via EDL and Fastboot),

And the risks you may face, from loss of warranty to build-up of the device, and we'll focus on the nuances of the Mi 7 (codenamed dipper), because the bootloader has specific features compared to newer devices.

What Does “This Device Is Locked” Mean on Xiaomi Mi 7

The message “This device is locked” is a bootloader lock indicator. The bootloader is a low-level software that runs to the operating system and checks firmware integrity. On Xiaomi devices (including Mi 7), the bootloader is blocked by default to:

• 🔒 Preventing the installation of informal firmware (custom) ROM), which may disrupt the system.
• 🛡️ Protection against malware that can modify system partitions.
• 📱 Preservation of warranty obligations (unblocking will cancel warranty in most regions).
• 🔄 Update control: Xiaomi distributes firmware through official MIUI Updater by blocking third-party sources.

On the Mi 7 (as with other models with the Snapdragon 845), the lock is implemented through the Anti-Rollback (ARB) mechanism.This means that even if you unlock the bootloader, trying to roll back to the older version of MIUI can lead to a complete locking of the device ("brick"). For example, if your Mi 7 was running on MIUI 12 and you try to flash MIUI 10, the system will lock the bootloader permanently.

It is important to distinguish “This device is locked” from other error messages: “This device is corrupted” indicates firmware damage (reflashing is required), “This device is unlocked” – the bootloader is already unlocked (you can install custom firmware).

On the Mi 7, a lock message can appear in two scenarios:

after a failed firmware or when trying to boot in Fastboot mode with a blocked bootloader.

The reasons for the lock on Xiaomi Mi 7

Locking the bootloader on the Xiaomi Mi 7 does not occur by itself – it is always preceded by one of the following actions:

The most dangerous case is the Anti-Rollback. For example, if your Mi 7 was originally running a MIUI 9 and you upgraded to MIUI 12, then trying to return to MIUI 10 will lead to irreversible lockdown, in which case even official Xiaomi tools will not help - you will need to solder the eMMC chip (which is not economically feasible).

⚠️ Note: If the lock occurred after the update MIUI Updater, don't try to unlock the bootloader right away. First, check if you can restore the device via Fastboot with data storage. Using the Mi Unlock Tool erases all user files!

Another common reason is that you're using TWRP or OrangeFox Recovery incorrectly, and if you've installed custom recoveries on a locked bootloader, the system might see this as an attempt to hack and activate the lock, and then only a complete reflash through MiFlash will help.

The official way to unlock through Mi Unlock Tool

The only legal method to unlock the bootloader on the Xiaomi Mi 7 is to use the Mi Unlock Tool utility from the manufacturer.

• 📱 Devices with a Mi Account (mandatory confirmation) SMS/email).
• 🔗 Internet connection (to verify account status).
• 🖥️ Windows computer (official utility does not work on the computer) macOS/Linux).
• 🔌 Cable. USB (It is desirable to be original, as cheap cables can cause connection errors).

Step-by-step:

1. Activate USB debugging: Go to Settings → About Phone → MIUI version and tap 7 times on the line to turn on Developer Mode. Then in Settings → Additional → For developers, turn on USB debugging and OEM unlock.
2. Link your Mi Account: In the same Developer Menu, find Mi Unlock Status and link your account. Without this step, the utility will not allow unlocking.
3. Download Mi Unlock Tool: The official utility is available on the Xiaomi website (version for Mi 7 - no lower than 5.5.224.24).
4. Launch the utility in Fastboot: Turn off the phone, press Volume Down + Power to log into Fastboot. Connect to your PC and follow the instructions in Mi Unlock Tool.
5. Wait 72-720 hours: Xiaomi enters a delay before unlocking (from 3 to 30 days depending on the activity of the account).

The Mi 7 (as with other models before the Mi 9) has a 360-hour waiting rule for new accounts, and if your Mi Account is registered less than 30 days ago, unlocking will be available only after 15 days, and the utility can give out errors:

• Cann’t unlock – the account is not linked to the device.
• Current account is different from the account info on the device.
• Device is not supported – the utility is outdated (download the latest version).

⚠️ Note: After successful unlocking, the Mi Unlock Tool will automatically perform a full Factory Reset!

Create a backup copy of the data|Charge your phone at least 60%|Download the latest version of the Mi Unlock Tool|Link Mi Account to Developer Settings|Prepare original USB-cable-->

Alternative Unlocking Methods (Fastboot and EDL)

If the official method does not work (for example, due to an Anti-Rollback error or lack of access to Mi Account), you can try to bypass the lock via Fastboot or EDL (Emergency Download Mode) modes.

Method 1: Fastboot firmware (for a locked bootloader)

If the bootloader is locked, but the device is defined in Fastboot, you can try flashing stock firmware through MiFlash.

• 📌 Anti-Rollback is not activated on the device.
• 📌 You are using the same or newer version of the firmware that was installed earlier.
• 📌 You have access to a Windows PC and MiFlash utility.

Instructions:

1. Download the official firmware for Mi 7 (select region and version of Fastboot).
2. Unpack the archive in a folder without Cyrillic characters (for example, C:\mi7_fastboot).
3. Install Qualcomm and MiFlash drivers (available in the firmware archive).
4. Connect your phone in Fastboot mode and start MiFlash.
5. In the utility, select the firmware folder, press Refresh, then Flash (Clean All option).

If the process is successful, the device will reboot to the stock MIUI. If an Anti-Rollback error occurs, further action is useless - repairs at the iron level will be required.

Method 2: Unlocking through EDL (for power users)

EDL (Emergency Download Mode) allows you to bypass the bootloader, but requires:

• 🔧 Special cable (EDL cable) or circuits of the circuit board.
• 💻 QFil or MiFlash programs with support EDL.
• 📄 Firmware in.mbn format (for Qualcomm).

On the Mi 7, the EDL is entered through the closure of test points on the motherboard or by using the command:

adb reboot edl

However, this method is not recommended for beginners, as:

• 🔴 Risk of damage to the fee when closing contacts.
• 🔴 Xiaomi could be blocked IMEI squashing EDL.
• 🔴 Paymentable instruments are required (for example, QC Firehose).

⚠️ Attention: Firmware through EDL Mi 7 with activated anti-Rollback will result in a total loss IMEI and the inability to use the mobile network. IMEI You can only use a service center with official access to the Xiaomi database.

What to do if the unlocking fails

If none of the methods worked, it’s possible that your Xiaomi Mi 7 fell under one of the following scenarios:

If your Mi 7 doesn’t respond to any commands in Fastboot, try:

1. Connect to another USB-port (preferably) USB 2.0 on the back of the PC).
2. Use a different cable (original from Xiaomi).
3. Run MiFlash on behalf of the administrator.
4. Check if the device is detected in Device Manager (Qualcomm HS-USB QDLoader 9008 for EDL should appear).

If the device does not turn on at all (even the indicator does not burn), the problem may be in the hardware: the battery is discharged (connect to charging for 30 minutes), the battery plume is damaged (disassembly is required), the power controller is burned (repair is needed).

1. Press Win + X, select Device Manager.

2. Find the Xiaomi Mi 7 in the list, right-click → Update the driver → Search on this computer → Select from the list.

3. Install the driver manually from the folder with MiFlash.-->

Risks and consequences of unlocking the loader

Unlocking the bootloader on the Xiaomi Mi 7 gives freedom to install custom firmware and modifications, but also entails a number of risks:

• 🚫 Loss of warranty: Xiaomi cancels warranty obligations when unlocked.
• 🛡️ Security vulnerabilities: Open bootloader allows malware to modify system files.
• 🔄 Problems with OTA-Updates: After installing custom recavator (TWRP) Official updates can break the system.
• 📵 Loss of loss IMEI: Wrong firmware through EDL Can reset the serial numbers of communication modules.
• 💥 «Device Brick: Firmware errors can result in complete inoperability (required) JTAG-repair).

The Mi 7 is particularly critical of Anti-Rollback. For example, if you unlock the bootloader and install LineageOS 16 (based on Android 9) and then try to return to MIUI 11 (also Android 9, but with the newer ARB), the device locks forever.

Also, remember that after the release:

• 🔐 Widevine L1 may degrade to L3, What will make streaming worse on Netflix, Disney+ and other services.
• 📱 Banking applications (for example, Sberbank Online) can block work on unlocked devices.
• 🔋 Battery optimization may deteriorate due to lack of stock algorithms MIUI.

⚠️ Warning: If you plan to sell the Xiaomi Mi 7 after unlocking, be sure to return the stock firmware and lock the bootloader back.Buyers often check lock status through Fastboot (fastboot oem device-info command), and an unlocked device may raise suspicions.

💡

On the Xiaomi Mi 7, unlocking the bootloader irreversibly activates Anti-Rollback for new firmware.This means that after upgrading to MIUI 12, you will no longer be able to return to MIUI 10 or lower – only on versions with the same or newer ARB level.

How to avoid blocking in the future

To avoid the message “This device is locked” on the Xiaomi Mi 7, follow these rules:

1. Do not update "on automaton": Before installation OTA-Check user reviews on the forums (4PDA, XDA). Some updates MIUI contain bugs that lead to blocking.
2. Use only official firmware: Download Fastboot/Recovery-Firmware only from the official website. Avoid "modified" versions from third parties.
3. Do not edit system partitions: Changing files to /system or /vendor (for example, through Magisk or Root Explorer) can cause damage to the bootloader.
4. Backup: Before any manipulation, save the NANDroid backup via TWRP or copy important data to your PC.
5. Check status. ARB: Before rolling back to the old version MIUI Check the Anti-Rollback level in the file /vendor/build.prop (parameter ro.vendor.build.security_patch).

If you’re actively experimenting with firmware, consider buying a second test device. The Xiaomi Mi 7 is a reliable smartphone, but its Anti-Rollback makes it vulnerable to irreversible locks. The alternative is models with an unlocked bootloader out of the box (for example, the POCO F1 for the international market).

To check the current lock status, type in the command to Fastboot:

fastboot oem device-info

If the answer is Device unlocked: false, the bootloader is locked. Once unlocked, this option will change to true.

FAQ: Frequent questions about blocking Xiaomi Mi 7