Xiaomi Redmi Note 9S remains a popular device due to its excellent balance of performance and price, but over time the software requires updating. Owners often face the need to upgrade to a new version of MIUI to get fresh security patches, improved battery optimization and new interface features. The upgrade process can seem difficult for a beginner, but when following the sequence of actions it does not cause difficulties.
There are several ways to install a new version of the operating system, ranging from a standard air update to manual installation through a computer, depending on the current firmware version, device region and user goals. It is important to understand that installing a global version on a Chinese device or vice versa requires unlocking the bootloader, which is a more complex procedure.
In this article, we will discuss all the preparation steps, updates and possible solutions to problems. You will learn how to save your data, where to download official files and how to avoid errors in the firmware process. Attention: before starting any manipulations, be sure to create a full backup of all important data to an external medium or to the cloud.
Preparing the device for system update
Before you start upgrading, you need to make sure that the device is fully ready for the procedure. Ignoring the preparatory stage can lead to data loss or software failures. First of all, check the battery level: it should be at least 60%, and it is better to charge the smartphone to 100%. In the process of installing new files, the system consumes a significant amount of energy, and a sudden shutdown can be fatal.
The second critical step is to free up space in internal memory. Firmware files weigh between 2 and 4 gigabytes, but the system requires significantly more free space to properly unpack and install. It is recommended to have a minimum of 10 GB. If memory is scarce, delete unnecessary apps, photos or transfer them to your computer.
It is also worth checking the stability of the Internet connection if you plan to upgrade via Wi-Fi. An unstable signal can interrupt the download of the service pack, which will result in a file integrity check error. For manual installation via a computer, make sure that the USB cable is serviceable and capable of transmitting data, not just charging the device.
☑️ Firmware readiness
Official Update via the Settings Menu (OTA)
The easiest and safest way to upgrade the Redmi Note 9S is to use the built-in OTA (Over The Air) feature, which does not require a computer or any special knowledge, and the system itself checks for a new firmware version that is suitable for your region and model and offers to download it.
To start the process, go to Settings → About Phone. At the top of the screen, you will see the MIUI version logo. Click on it and the system will start looking for updates. If a new version is found, the Download button will appear. Once the file is uploaded, click Reboot and Update. The device will turn off and the installation process will begin.
Sometimes the system may not offer an update, but it's already out for your region, so you can click on the three dots in the top right corner of the screen and select "Select a firmware file." This will allow you to manually specify the archive you downloaded in advance, but we'll talk about this in the next section. The standard OTA path is ideal for those who want to minimize risks.
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If the update doesn’t come, try changing your region in your settings (like India or Indonesia), checking for an update, and then returning your region back.
Manual installation of firmware through Recovery
The method of manual installation through Recovery is suitable for cases where OTA-The update doesn’t work, or you want to upgrade to a specific version that the system doesn’t automatically offer yet. To do so, you’ll need a.zip firmware file that must strictly match your device model and current firmware type (Global, EEA, Russia).
Download the current firmware archive from the official website or a trusted source. Place the file in the root of the smartphone's internal memory. Next, go to Settings → About the phone, click on the MIUI version and select three dots in the corner. From the menu, select "Select firmware file" and specify the downloaded archive. The system will check the file and suggest a reboot.
⚠️ Note: If you try to install an older version of the firmware or a version for another region without the unlocked bootloader, the system will issue a “Can’t verify update” error and refuse to continue installing it.
There is also a hidden Recovery mode available through the engineering menu, which requires you to quickly click on the version number in the update menu several times to activate it. Once the "Additional Features Enabled" message appears, you can select a firmware file. In the window that opens, select "Select File" and specify the archive. Click the "Update" button to start the process.
What if Recovery says “Zip file signature verification failed”?
Fastboot Firmware with Mi Flash Tool
The most powerful tool for working with Xiaomi software is the Mi Flash Tool for PC, which allows you to perform a “clean” installation of the system, which is especially useful when switching between regional versions (for example, with the help of the “clean” system). CN Global) or when you restore a brick. This method requires a firmware file in.tgz format (unpacked) and drivers installed. ADB/Fastboot.
Before you start, you need to unlock the bootloader through Mi Unlock. Without this step, you can't run the firmware through Fastboot. After you unlock, turn the phone off and on in Fastboot mode, pressing both the power and volume buttons together. Connect the device to your computer with a USB cable.
Run the Mi Flash Tool, press the Refresh button to detect the phone. En route to the files, specify the folder with the unpacked firmware. At the bottom of the window, select the firmware mode: clean_all (complete data cleansing) or save_user_data (Save data, only when you update within a single region. Click Flash and wait for the process to be completed.
| Firmware mode | Data retention | Risks. | Recommended use |
|---|---|---|---|
| clean_all | No (full reset) | Minimum | Changing the region, treating errors |
| save_user_data | Yes. | Medium (file conflicts) | Update version in one region |
| clean_all_lock | No. | High (locking) | Only for service centers |
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Use of the regime clean_all when changing the firmware region is a prerequisite for the correct operation of the system and avoid cyclical reboots.
Solving Common Errors During Updating
During the update process, users of Xiaomi Redmi Note 9S may encounter various errors, one of the most common is the message "Backage damaged" or "Can not check the update", most often this is due to incomplete file download or violation of the integrity of the archive, the solution is simple: delete the file and download it again, preferably through a wired connection or stable Wi-Fi.
Another common problem is getting stuck on the Mi logo (bootloop) after installation. This can be due to a conflict of system files when updating without clearing the data. If the phone doesn't boot for more than 10 minutes, try entering Recovery mode and resetting to factory settings (Wipe Data).
If your computer doesn't see your phone in Fastboot mode, check Windows Device Manager. The device may appear as "Unknown Device." In this case, you need to manually install Qualcomm or Xiaomi drivers. USB Driver, try replacing it. USB-cable or connect the phone to another USB-port, preferably directly to the motherboard, bypassing the hubs.
- 📉 Error 7 in the Mi Flash Tool usually indicates problems with access rights or file paths – move the firmware folder to the root of the C disk:.
- 🔒 The message “Device is locked” means that the bootloader is locked, and installing global firmware on the Chinese version is impossible without unlocking.
- 🔋 If the phone is turned off while you are firmware, try charging it off for an hour, then plug it back into the PC.