How to format a memory card on Xiaomi Redmi 9: a complete guide with nuances

Xiaomi Redmi 9 is one of the most popular budget smartphones, which is still actively used due to balanced characteristics and support for updates. However, over time, owners face the need to clean or reformat the memory card — whether it is slow work, read errors or preparing to use as an internal drive. Unlike flagship models, Redmi 9 has its own features with microSD, which is important to consider to avoid data loss or damage to the card.

In this article, we’ll look at all formatting methods, from standard through phone settings to low-level cleaning with a PC, and explain which file system to choose (FAT32, exFAT or NTFS) depending on the task. We’ll focus on the hidden nuances of MIUI 12/13 that can block formatting without first taking action. If your card is defined as “damaged” or your phone asks you to format it each time you connect, here’s the solution.

Preparing for Formatting: What to Do Before Cleaning the Map

Before you start formatting, be sure to back up all the important data. Even if the card seems to be working, the cleaning process can go wrong — especially if you use it as an internal drive (Adoptable Storage function in MIUI), in which case the phone encrypts the data, and after formatting it will be impossible to restore it.

Here’s what to check before you start:

• 📱 Determine the type of card: Redmi 9 supports microSD up to 512 GB (officially), but in practice, work and cards for 1 TB – however, with possible lags when writing large files.
• 🔋 Battery charge: if the phone runs out during formatting, the card may become unreadable.Recommended level is at least 50%.
• 🔄 Check the card for errors: connect it to your PC and run the utility chkdsk (for Windows) or fsck (for Windows) Linux/Mac). This will help to identify the bad sector.
• 📁 Make sure the card is not used: Close all apps that may access it (e.g. gallery, music players or cache-only messengers). SD).

⚠️ Note: If the card was previously used as an internal memory (Adoptable Storage), it cannot be formatted with standard means. MIUI. First, mount it in the storage settings, otherwise the system will give an error "Can not format".

Method 1: Formatting through phone settings (the easiest method)

This is a basic method that is suitable for most users, it does not require a PC connection and works even if the card is detected with errors (but not if it is completely "raw" or not recognized by the system). MIUI 12/13/14 on the Redmi 9:

1. Open the Settings app (the gear icon on the desktop).
2. Go to Memory (or Storage in newer versions of MIUI).
3. At the bottom of the screen, tap the Memory Map item (if it is not available, check if the card is inserted correctly into the slot).
4. In the upper right corner, press three dots (⋮) and select Storage Settings.
5. Tap to format. → Clean and format.
6. Confirm the action, wait until the completion (usually takes 1-3 minutes).

By default, the phone will offer a FAT32 file system – it is compatible with most devices, but has a file size limit (maximum 4GB). If you plan to record video in 4K or large archives, choose exFAT (available only for cards with a capacity of 64GB).

⚠️ Warning: If the card is undetectable after formatting, try removing it and pasting it back in. Sometimes the contacts of the Redmi 9 slot oxidize — wipe them with an alcohol napkin.

Method 2: Formatting via PC (for cards with errors or large volumes)

If the phone refuses to format the card (issues an error "Team not fulfilled" or "SD-This is a method that is also useful if you want to choose a file system. NTFS (For example, to write files more than 4 GB on cards up to 32 GB).

You'll need:

• 💻 Computer with Windows, macOS or Linux.
• 🔌 Card reader (built into a laptop or external card reader) USB-adapter).
• 🛠️ Low-level formatting software (optional if standard tools do not help).

Instructions for Windows:

1. Insert the card into the card reader and connect to the PC.
2. Open This Computer (My Computer) and find a removable disk (usually D:, E: or similar).
3. Right-click on the disk → Format...
4. Select the file system: FAT32 for compatibility with all devices (but a 4GB limit per file); exFAT for 64GB cards (optimum choice for Redmi 9); NTFS – only if the card is used ONLY with this phone and PC (MIUI doesn’t always work correctly with NTFS).

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If Windows says, "Windows fails to complete formatting," use the SD Formatter utility (the official program from the SD Association) or the HP USB Disk Storage Format Tool, which often works where standard tools are powerless.

Method 3: Low-level formatting (to recover damaged cards)

If a memory card is “raw” (defined as RAW), standard formatting won’t help — it requires a complete rewriting of sectors, using specialized utilities that erase data at the physical level. Importantly, this method destroys everything without recovery and can shorten the life of the card (especially if it is already worn out).

The best low-level formatting programs:

The HDD Low Level Format Tool is used:

1. Connect the card to the PC.
2. Start the program (administrator rights are required).
3. Select your card from the list of devices (be careful – the wrong choice will lead to loss of data on another drive!).
4. Click Continue → go to the LOW-LEVEL FORMAT tab.
5. Press. FORMAT THIS DEVICE and wait until it is completed (may take several hours for large-volume cards).
6. After low-level formatting, do the usual (via Windows or SD Formatter).

How to set up:

1. Put the card in the phone.
2. Go to Settings → Memory → Memory Map.
3. Tap to set up → Internal memory.
4. Follow the instructions on the screen. The phone will prompt you to format the map (exFAT file system will be selected).
5. After formatting, select which data to transfer to the map (applications, photos, files).

Important: once you activate Adoptable Storage, you can't just take the card out, it'll cause app malfunctions, so you can get it back to normal.

1. Go to Settings → Memory → Memory Map.
2. Tap Data Transfer and Formatting → Format as a portable device.
3. Confirm the action. All data from the map will be deleted!

FAQ: Answers to Frequent Questions