How to reflash Xiaomi Redmi Note 9: 3 proven ways

Xiaomi Redmi Note 9 remains one of the most popular budget smartphones even years after its release. But over time, factory firmware begins to slow down, and updates through MIUI Updater stop coming. Flashing the device can return to its former performance, install a fresh version of Android or even switch to custom firmware like LineageOS. However, the process has nuances, from unlocking the bootloader to choosing the right version of software for your modification (Redmi Note 9 Mercurio, Note 9S Curtana or 9 Pro Joyeuse).

In this article, we will analyze three official methods of firmware - through MIUI Updater, Recovery and Fastboot - and also tell you how to avoid errors like Error: Critical Partition Flashing is Forbidden or hanging on the Mi logo. Particular attention will be paid to preparation: without a properly unlocked bootloader and backup of data, even the most reliable instructions will not save you from the "brick".

1. Firmware Preparation: What to Do Before Starting

Flashing without preparation is like repairing a roof in the rain. Before touching the Redmi Note 9 system files, follow the mandatory steps:

• 🔋 Charge the battery to minimum. 60%. When discharged during firmware through Fastboot, the smartphone can turn into a “brick” with an error BROM Error: S_FT_ENABLE_DRAM_FAIL (0xC0030004).
• 📱 Save it. IMEI. To do this, enter the code *#06# in the phone application and write down both numbers (if you have a model with two). SIM). When the firmware is bad IMEI may be.
• 🔐 Unlock the bootloader (if you haven't done it before) without it, you can't run the Fastboot or install custom Recovery.
• 💾 Create a backup through Settings → Additionally. → Backup and reset. Alternative is the Mi program PC Suite for Windows.

Critical detail: Redmi Note 9 models for different regions have unique firmware. For example, the firmware for Mercurio (global) will not work for Curtana (Indian version). To find out the exact modification, go to Settings → About Phone → MIUI version and look at the Model string. Also check the device code with the team in ADB:

adb shell getprop ro.product.device

⚠️ Note: If your Redmi Note 9 is purchased in China (suffixed model) CN), A global firmware version may block the network due to differences in modem modules, in which case a patch for nvram will be required.

2. Method 1: Firmware via MIUI Updater (without PC)

The safest method, but with limitations: it only allows you to upgrade to the latest official version of MIUI for your region.

Instructions:

1. Open Settings → About the phone → System update.
2. Click on the icon"⋮" (three dots) in the upper right corner and select Select firmware file.
3. Specify the path to the downloaded firmware file (should have a.zip extension and weigh ~2-3 GB).
4. Confirm installation. The phone will reboot to Recovery and start the process.

The official files for the Redmi Note 9 are available at MIUI Downloads. Choose the Stable (stable) or Developer (weekly updates) version depending on your needs. Pay attention to the Region column - it should match your model!

⚠️ Warning: If you've got your phone stuck on the Mi logo after you've run it through Updater, don't panic. Wait 10-15 minutes -- sometimes it takes a long time to load the first one. If the screen doesn't change for more than 20 minutes, try clamping the power. + Volume up to go to Recovery and reset (Wipe Data).

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Firmware via MIUI Updater does not reset user data, but it is recommended to make a backup in case of a failure.

3. Method 2: Firmware through Recovery (reset is not required)

This method is suitable for installing official MIUI firmware without using a PC. Unlike Fastboot, it does not require unlocking the bootloader, but has a limitation: the firmware version must be newer or the same as the current one. Downgrade through Recovery will lead to an error.

Step-by-step:

Download firmware (.zip) for your model |Rename the file to update.zip (optional, but recommended) |Transfer the file to the root of internal memory |Disable password/fingerprint protection (in case of failure) |Recharge the phone to at least 50%

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1. Turn off the phone and press Power + Volume up to enter Recovery.
2. Select the language (if available) and tap Install update.zip to System.
3. Confirm the installation. It'll take 5-10 minutes.
4. After you complete the process, select Reboot → System.

If the Recovery menu doesn't have Install update.zip, you have customized recoveries (e.g. TWRP).

1. Choose Install.
2. Specify the path to the firmware file.
3. Swipe to confirm Flash (Swipe to confirm Flash)
4. After installation, run Wipe → Format Data (if you need a reset).

4. Method 3: Firmware via Fastboot (full reset)

The most powerful, but also the most risky method.

• 🔄 Restore the phone after the “brick” (if the bootloader is not damaged).
• 📉 Downgrade the version MIUI (Like 14th to 12th).
• 🔧 Install firmware for another region (with the risk of network loss).

The work will require:

• Windows 10/11 PC (Linux/Mac may have driver issues)
• The Mi Flash Tool (download from the official website)
• Firmware in.tgz or.zip format (not to be confused with.tgz) OTA-update!).
• USB Type-C cable (preferably original)

Instructions:

1. Unpack the firmware archive in a folder without Cyrillic characters (for example, C:\MIUI\).
2. Turn off the phone and press Power + Volume down to enter the Fastboot (the image of a hare in a hat-eared will appear).
3. Connect your phone to your PC. Install drivers if Windows is making an error.
4. Launch the Mi Flash Tool, press Select and specify the folder with the firmware.
5. At the bottom, select Clean All mode (full reset) or Save user data (save data, but doesn’t always work).
6. Press Flash and wait until it is completed (5-15 minutes).

⚠️ Note: If the Mi Flash Tool gives an Error: Flash is not done, check if the firmware folder is correctly selected (must be files) flash_all.bat, images/). Is the bootloader unlocked (checked by the fastboot oem device-info command - Device unlocked: true). USB-Hub (connect directly to the PC port).

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If the phone doesn't turn on after you've run through Fastboot, try pressing the power button for 20-30 seconds. Sometimes flash again with Clean all mode helps.

5 Unlock the bootloader: without it can not do

To run through Fastboot or install custom Recovery (such as TWRP), you need to unlock the bootloader. Xiaomi made this process more difficult in 2023, but it is still possible.

1. Link your Mi Account to your phone: Settings → Xiaomi Account → Sign in.
2. Activate USB debugging: Settings → About Phone → MIUI version (tap 7 times), then go back to Additional → For Developers → Debugging by USB.
3. Connect your phone to your PC and execute in ADB: adb reboot bootloader
4. On PC, launch the Mi Unlock Tool (download from the official website) and log in to the same Mi Account.
5. Wait 72–168 hours (3–7 days) Xiaomi blocks unlocking immediately after the account is linked.
6. After the deadline, repeat steps 3-4 and press Unlock.

Important nuances:

• 📅 Standby time (72/168 hours) reset if you untie your account or drop your phone.
• 🔗 Mi Account must be linked to phone number (unblocking is not possible without this).
• 🔄 After unlocking all data on the phone will be erased.

6. Solving common firmware errors

Even with the exact following of the instructions, problems can arise.

If the phone doesn’t turn on at all (black screen, no button response), try:

1. Charge it for 30–60 minutes (sometimes a discharged battery blocks the onset).
2. Press Power + Volume down for 20 seconds (forced rebut).
3. Connect to a PC and check if Device Manager defines Qualcomm HS-USB QDLoader 9008 (EDL mode).

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90% of the bricks are recovered through Fastboot or EDL. The main thing is not to panic or try to flash again without diagnosis.

7.Castom firmware: is it worth the risk?

Official MIUI firmware is not popular with the public because of advertising, restrictions and Chinese chips, and the alternative is custom firmware like:

• 📱 LineageOS – “clean” Android without unnecessary applications.
• 🔥 Pixel Experience – The interface is like Google Pixel.
• ⚡ Havoc-OS – Maximum customization.
• 🛡️ ArrowOS – balance between stability and features.

However, before installation, consider:

• ⚠️ No official support - bugs and glitches are corrected by enthusiasts.
• 📶 Network problems – some firmware does not run VoLTE or 4G.
• 🔋 Fast discharge – energy optimization is worse than in the MIUI.
• 🔒 No. OTA-Updates – you will have to manually re-check.

If you do, the algorithm is as follows:

1. Unlock the bootloader (see section 5).
2. Install TWRP Recovery via Fastboot: fastboot flash recovery twrp.img fastboot boot twrp.img
3. In TWRP, run Wipe → Format Data → Yes (this will erase everything, including internal memory!).
4. Transfer the firmware to the phone via MTP (TWRP has this mode).
5. Install firmware, then Gapps (if you need Google services) and Magisk (for root rights).

⚠️ Note: Redmi Note 9 with Mediatek Helio processor G85 (Mercurio models) some custom firmware may not start due to kernel driver issues. Check compatibility on the XDA-Developers forum before installing.

FAQ: Answers to Frequent Questions