Xiaomi Redmi 9 firmware: official and unofficial installation methods

Xiaomi Redmi 9 remains one of the most popular budget smartphones even years after its release. But over time, standard MIUI firmware begins to slow down and updates stop coming out, in which cases users are looking for ways to reflash the device — whether it is the official global version, custom firmware like LineageOS or Pixel Experience, or roll back to a stable build.

In this article, you will find step-by-step instructions for all the current ways to run Redmi 9 firmware (codenamed lancelot), including unlocking the bootloader, installing via Fastboot and Recovery, and solving typical errors. We will break down the nuances for different versions of the device (Redmi 9, 9A, 9C, 9T) and warn against common errors that can turn the phone into a “brick”.

⚠️ Important: Smartphone firmware is a process that requires care. Errors at the stage of unlocking the bootloader or choosing the wrong version of the software can lead to loss of warranty, blocking. IMEI If you're not sure what you're doing, call a specialist.

1. Firmware Preparation: What You Need to Know Before You Start

Before you start firmware, make sure your device meets the requirements. Xiaomi Redmi 9 has several modifications, and firmware from one model (for example, Redmi 9T) is not suitable for another (Redmi 9 Prime).

Highlights:

• 🔍 Check the code name of your device. To do this, go to Settings. → The phone. → Version. MIUI and tap 7 times on the "Core" line. In the menu that opens, look for the Device option (should be a lancelot for Redmi 9).
• 🔋 Charge the phone at least 60%. interruption of the process due to battery discharge can lead to the inability to recover using standard methods.
• 📱 Back up your data. Firmware erases internal memory! Use Mi Cloud, Google Drive, or physical copying on your PC.
• 🖥️ Prepare a PC with Windows 10/11 (for the Fastboot method) or Linux/macOS (for ADB). Macs may require additional drivers.

Also check if you have a bootloader unlocked. If you turn on the phone with the downside + power button pressed, you see this device is locked - it must be unlocked (instructions in the next section).

2 Unlock the bootloader on Redmi 9

Without an unlocked bootloader, you won’t be able to install custom software or even official firmware through Fastboot. Xiaomi requires confirmation of the Mi Account account tied to the device and wait 72–168 hours after submitting an application.

Step-by-step:

1. Link Mi Account to your phone: Settings → Xiaomi Account → Sign in.
2. Activate. OEM Unlock and Debugging by USB: Go to Settings. → The phone. → Version. MIUI and tap 7 times on the line to turn on Developer Mode. → Additionally. → For developers and include: 🔓 OEM Unlock (unlocking the bootloader) 🐛 Debugging by USB

Mi Unlock Tool

Fastboot

Loudness down + Nutrition

Mi Unlock Tool

Mi Account

Couldn’t unlock

⚠️ Note: Once the bootloader is unlocked, all information, including photos and apps, will be erased from the phone, and Xiaomi can block the ability to unlock if the device was purchased less than 30 days ago or linked to another account.

3.Redmi 9 firmware methods: which one to choose?

There are three main methods of installing firmware on Redmi 9. The choice depends on your goals:

For beginners, we recommend Recovery (if you need to update the official MIUI) or Fastboot (if you need to reflash to another region-version).Savvy users can try custom firmware through TWRP, but this requires additional manipulation with ADB and Magisk (for root rights).

💡

If you're flashing your phone for the first time, start with the official global firmware (MIUI Global Stable).Castom builds can contain bugs, especially on budget devices with the Helio G80.

4. Firmware through Recovery (without unlocking the bootloader)

This method is suitable for installing official updates. MIUI It does not require unlocking the bootloader and is suitable for rolling back to the previous version or correcting errors after a failed one. OTA-update.

Instructions:

1. Download the firmware from the official Xiaomi website. Choose the version for lancelot (for example, V12.5.3.0.RJCMIXM for global stable).
2. Rename the file to update.zip and place it at the root of the phone’s internal memory (not in folders!).
3. Turn off the phone and press Volume Up + Power to enter Recovery Mode.
4. In the recovery menu, select the language (if available: 📁 Choose Install. update.zip to System. ⏳ Wait for the process to be completed (5–10 minute). 🔄 Reboot your phone (Reboot to System).

⚠️ Note: If after firmware the phone is stuck on the logo MI longer than 15 minutes – perform hard reset (click Volume Up) + Nutrition → Wipe Data. This will delete all the data, but it will bring the phone back to working order.

5. Fastboot (Mi Flash Tool)

Fastboot is used to completely flash the device, including changing the region (for example, from Chinese firmware to global).

Step-by-step:

1. Download the firmware in.tgz format for lancelot (for example, lancelot_global_images_V12.5.3.0.RJCMIXM_20220321.0000.00_11.0_global_5a4a3a3a4e.tgz).
2. Unblock the file to a short-track folder (e.g., C:\MIUI\).
3. Download and install the Mi Flash Tool.
4. Turn off the phone and put it in Fastboot mode (clip Volume Down + Power).
5. Connect the device to your PC and run the Mi Flash Tool. The program must define the phone as a COM-port.
6. In Mi Flash Tool, press Select and specify the path to the unpacked firmware: 🔄 Clean all – complete cleaning (recommended when changing region). 🗃️ Clean all and lock - cleaning + Loader lock (only for official firmware!). 🚫 Save user data – saving data (not always working correctly).

Flash

⚠️ Note: If the Mi Flash Tool gives an error critical partition flashing is not allowed, then you are trying to flash an unofficial or inappropriate version. MIUI. Use only firmware from the Xiaomi website for the Lancelot model!

💡

Clean all and lock mode will lock the bootloader back, only use it if you are sure you will no longer install custom firmware.

6. Install custom firmware (TWRP + ADB)

Custom firmware like LineageOS or Pixel Experience allows you to get a “clean” Android without a MIUI shell, but require an unlocked bootloader and install TWRP Recovery.

Instructions:

1. Download: 📱 TWRP for lancelot (e.g. for lancelot, twrp-3.7.0_9-0-lancelot.img). 🤖 Custom firmware with XDA Developers (e.g. LineageOS) 20 lancelot). 🔑 Magisk (if you need root rights).

ADB and Fastboot

Android SDK Platform Tools

Fastboot

ADB

fastboot flash recovery twrp-3.7.0_9-0-lancelot.img


fastboot reboot recovery

The phone will reboot to TWRP.

TWRP

Wipe → Format Data

yes

Magisk

ADB Sideload

adb sideload lineage-20.0-20230612-nightly-lancelot-signed.zip

Magisk

Reboot System

⚠️ Attention: Redmi 9 with Android 11-based firmware+ may not work ADB Sideload due to Xiaomi restrictions. In this case, copy files to your phone via the phone MTP into TWRP (Connect your phone to your PC and select Mount → Enable MTP).

7.Typical errors and their solution

Even with the exact following of the instructions, there can be problems.

If none of the methods worked, try flashing your phone through the phone. EDL-This requires an authorized Xiaomi account and a Deep Flash Cable, a method that is risky and recommended only for experienced users.

FAQ: Frequent questions about Redmi firmware 9