How to upgrade Xiaomi Redmi 6 Pro to the latest version of MIUI: all ways

Xiaomi Redmi 6 Pro is one of the most popular budget smartphones of 2018, still in use by millions of users. Despite its age, the device continues to receive security and optimization updates through custom firmware and official patches from Xiaomi. However, the update process has nuances, from locking the bootloader to installing errors through Recovery.

In this article, you will find step-by-step instructions for all available updates: through Settings, Recovery, Fastboot, and even with the help of a PC. We will also analyze how to avoid errors (for example, Error 7 or hanging on the MI logo), and give recommendations on the choice of the version of the firmware - official MIUI or custom (LineageOS, Pixel Experience).

If your Redmi 6 Pro is slow, overheating, or doesn’t support new apps, a firmware update can solve these problems, but remember: improper firmware can lead to a device bric (complete failure), especially if you’re using informal builds without unlocking the bootloader.

1. Update Preparation: What to Do Before Firmware

Before proceeding with the update, follow the mandatory steps to avoid data loss or system damage:

• 📱 Check the current version MIUI: Go to Settings. → The phone. → Version. MIUI. Write down the assembly number (for example, V12.5.1.0.PDMMIXM).
• 🔋 Charge the battery to at least 60%.When upgraded via Recovery or Fastboot, discharging during the process may cause a failure.
• 📁 Create a backup: Use Settings → Additionally. → Backup or third-party utilities like Titanium Backup (requires root).
• 🔌 Prepare your cable and PC: If you plan to upgrade via Fastboot, check your health USB-cable (it is better to use the original cable).

Pay special attention to unlocking the bootloader. On the Redmi 6 Pro, it is locked by default, and installing custom firmware will require official permission from Xiaomi via the Mi Unlock Tool. The process takes up to 72 hours (related to Xiaomi's security policy).

⚠️ Note: If you are updating with MIUI 10 older MIUI 12+, You may need to reset your settings (Wipe Data) due to changes in the partition structure /data. Without it, the smartphone can boot into an endless cycle.

Method 2: Automatic Update through Settings (OTA)

The easiest and safest method is to upgrade over-the-air, suitable for official MIUI builds without a root and unlocked bootloader.

Instructions:

1. Connect to a stable Wi-Fi network (update via mobile Internet may be interrupted).
2. Go to Settings → About the phone → System update.
3. Click Check Updates. If a new version is available, a Download button will appear.
4. After download, click Set and confirm the reboot.

If the update is not available, it is possible:

• 🌍 Your region is not supported (e.g. global firmware for PDGMIXM It does not work for Russian devices).
• 🔄 Xiaomi servers are temporarily unavailable (check status on the official website).
• 📵 Device modified (Magisk installed or system files modified).

Check the Wi-Fi connection

Free up at least 2 GB of memory

Disable VPN/proxy

Close background annexes

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⚠️ Attention: If after OTA-Update smartphone stuck on the logo MI For more than 10 minutes, force it to restart (Power) + Volume Up for 15 seconds. If the problem recurs, reset via Recovery is required.

Method 2: Manual installation via Recovery (for official firmware)

If OTA doesn’t work or you want to install a specific version of MIUI, use manual firmware through Recovery.This method saves user data, but requires the right firmware file selection.

Steps:

1. Download the official firmware for Redmi 6 Pro (codename sakura) from MIUI ROM or the official portal. Choose the version marked Recovery (file with the.zip extension).
2. Move the file to the root folder of internal memory (not to folders!).
3. Turn off your phone and press Power + Volume Up to log in to Recovery.
4. Select the language (if required), then Install update.zip to System.
5. Confirm the installation and wait until the completion (usually 5-10 minutes).

If an Error 7 error appears during installation, it means that:

• You are trying to install firmware for another model (e.g. Redmi 6 instead of 6 Pro).
• The device is modified (TWRP installed or boot.img modified).
• The firmware version is lower than the current one (downgrade blocked).

4. Method 3: Fastboot Firmware (for power users)

The Fastboot method is used to:

• Restore the "bricked" device.
• Installation of official firmware from scratch (for example, after resetting).
• Recovery error bypass (e.g. Error 7)

This will require:

• 🖥️ Computer with drivers installed ADB/Fastboot (download).
• 🔌 Original. USB-cable (faulty cable is a common cause of errors).
• 📄 Firmware in.tgz format for Fastboot (download on the MIUI ROM).

Instructions:

1. Unpack the firmware archive in a folder on your PC (e.g., C:\MIUI\sakura).
2. Turn off your phone and press Power + Volume Down to enter the Fastboot (a hare in a hat-eared hat will appear).
3. Connect the device to your PC and check the connection with the command: fastboot devices must display a serial number.
4. Start the firmware script: fastboot flash-all.bat (for Windows or./flash_all.sh (for macOS/Linux).

⚠️ Note: If the process is interrupted during the flashing phase boot.img, Do not turn off the device! Repeat the command fastboot flash boot boot.img Manual. A common cause of failure is a conflict with the antivirus (turn it off before firmware).

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If the smartphone doesn’t turn on after you run through Fastboot, try pressing the Power + Volume Up for 30 seconds to force a reboot. If it doesn’t work, repeat the Fastboot erase userdata.

5. Method 4: Install custom firmware (LineageOS, Pixel Experience)

Official updates for the Redmi 6 Pro have stopped on MIUI 12.5, but the device is supported by custom firmware based on Android 11/12.

• 📱 LineageOS 18.1 (Android 11) - stable, without excess software.
• 🎨 Pixel Experience – The interface is like Google Pixel.
• ⚡ Havent OS — Optimized for weak devices.

Requirements:

• Unlocked boot loader (see instructions below).
• Installed custom recovery TWRP (Sakura version).
• Backup copy of EFS (folder with IMEI and modem settings).

Instructions:

1. Download firmware (for example, LineageOS from the official website) and GApps (if you need Google services).
2. Reboot to TWRP (Power + Volume Up)
3. Run Wipe → Advanced Wipe and mark Dalvik, Cache, System, Data.
4. Install firmware, then GApps, then Magisk (if root is needed).
5. Reboot. The first download can take up to 15 minutes.

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Custom firmware requires unlocking the bootloader, which resets the device to factory settings. All data will be deleted!

6. How to unlock the bootloader on Redmi 6 Pro

Xiaomi blocks the bootloader on all devices to protect against unauthorized changes. To install custom firmware, it must be unlocked through the official utility Mi Unlock Tool.

Steps:

1. Link your Mi Account to your device: Settings → Xiaomi Account → Sync.
2. Enable OEM Unlock and USB Debugging in Settings → For Developers.
3. Download the Mi Unlock Tool and install it on PC.
4. Turn off your phone and press Power + Volume Down to log into Fastboot.
5. Connect the device to your PC and start the Mi Unlock Tool. Sign in to your Mi Account.
6. Press Unlock. The process will take up to 72 hours (Xiaomi checks the request manually).

After unlocking:

• All data will be erased.
• The loader will remain unlocked even after reset.
• Some features (such as Mi Pay) may stop working.

⚠️ Warning: If a Couldn't unlock error occurs when unlocking, check: Mi Account is tied to the device for more than 72 hours. ADB. You are using the original cable (not the original cable) USB-hub!).

7. Frequent errors and their solutions

When you upgrade to Redmi 6 Pro, users are faced with typical problems.

If the IMEI has disappeared or the mobile connection has stopped working:

1. Check the integrity of the /efs folder through Root Explorer.
2. Restore the EFS backup (if you did it before the firmware).
3. Fastboot: fastboot flash modem NON-HLOS.bin (the file NON-HLOS.bin is in the firmware archive).

8. FAQ: Answers to frequent questions