How to open access to SD-Xiaomi Redmi Note 9: 5 working ways

Xiaomi Redmi Note 9 owners often face a problem when the smartphone does not see SD-This can be manifested in different ways: the memory card is not defined at all, files are not displayed in the Explorer, or a notification appears «SD-The reasons range from the banal (incorrect installation) to the technical (file system damage). In this article, we will discuss all the current methods of solving a problem, from basic checks to deep settings. MIUI.

The feature of the Redmi Note 9 (codename merlin) is a hybrid slot for memory cards: it is combined with the second. SIM-This means that when using two SIM cards, it is physically impossible to insert a microSD. If you still choose a memory extension, make sure that the card is compatible with the device (recommended class — UHS-I Next, we will look at step-by-step actions for different scenarios, from initial setup to data recovery.

1. Verification of physical connection SD-map

Before you dive into the software settings, eliminate mechanical problems. 30 percent of the time, access problems are not possible. SD-The card is associated with improper installation or contamination of contacts.

How to check:

• 🔹 Remove and reinstall the card: turn off the smartphone, get the tray for SIM-cards with a paper clip, check that the microSD is inserted face-up (contacts should be directed to the back cover of the phone).
• 🧹 Clean the contacts: wipe the gold pins of the card and slot in the phone with a dry soft cloth (such as microfiber!
• 🔄 Try another card: If you have a spare microSD, insert it to prevent the memory card itself from malfunctioning.

If you still don't know the card after this manipulation, you can go to software methods. Note: Redmi Note 9 supports cards up to 512 GB, but they must be formatted in FAT32 or exFAT to work properly.

2. Formatting SD-maps through settings MIUI

If the smartphone recognizes the card, but can not read the data (for example, a notification appears «SD-The simplest solution is formatting. Note that this will delete all files from the media! Before the procedure, copy important data to the computer.

Step-by-step:

1. Open the Settings → Memory.
2. Tap the line. SD-map (if it appears in the list).
3. In the upper right corner, press three dots (⋮) and select Storage Settings.
4. Select Format → Format as internal (if you want to use the card as a memory extension) or Format as portable (for normal file storage).
5. Confirm the action, wait for the process to be completed (may take up to 5 minutes).

Importantly, if you choose the "Like Internal" option, the card will be encrypted and tied to that device, and once removed, it will not be read on another smartphone or PC without being reset.

Save important data to your computer | Check battery power (minimum 50%) | Make sure the card is not used by apps |Close all programs that work with files-->

Correction of errors SD-PC-card

If smartphone formatting doesn't work or the card isn't even identified, plug it into your computer. You'll need a card reader (or microSD adapter). Windows uses the built-in chkdsk utility, and MacOS uses the Disk Utility.

Instructions for Windows:

1. Insert the card into the card reader and connect to the PC.
2. Open Command Prompt on behalf of the administrator (click Win + X → Command Prompt (Administrator)).
3. Enter the command: chkdsk X: /f /r where X is the letter of your disk SD-Check the cards (check in "This Computer»).
4. Wait for the check to be completed (it can take up to 30 minutes depending on the size of the card).

If the utility finds errors but can not fix them, try formatting the card via PC:

• 🖥️ Open "This Computer" and right-click on SD-map → Format.
• 📁 Select the file system FAT32 (If the card is up to 32 GB or exFAT (if more).
• ⚙️ Make sure the cluster size is set to 4096 bytes (by default).

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If the card is not formatted through standard Windows tools, use the SD Formatter utility from the SD Association, which restores even heavily damaged media.

4. Set up access rights in MIUI

Xiaomi Redmi Note 9 is sometimes seen» SD-The card, but blocks access to files due to restrictions MIUI. This can be manifested in the inability to write data or open certain folders, the solution is to allow access manually.

How to set up rights:

1. Go to Settings → Applications → Permissions → Storage.
2. Find the application you want to give access to (such as “Gallery” or “Files”) and tap it.
3. Activate the switch. SD-map.
4. If the option is inactive, go back to Settings. → Memory. → SD-map → Settings of the storage and select Change (if available).

Applications that do not appear in the permission list (such as third-party file managers) may need to manually specify the path to the permission list. SD-Most managers do this through the app settings: open the side menu. → Settings → Folders. → Add a path and point out /storage/XXXX-XXXX (where XXXX-XXXX — Your unique card ID).

5. Resetting and updating MIUI

If none of the previous methods worked, the problem may lie in software failures MIUI, in which case will help reset settings (without deleting data) or update firmware.

How to update MIUI:

• 📱 Go to Settings. → The phone. → Update MIUI.
• 🔍 Click on “Check Updates” and install the latest version available.
• 🔄 If the update is not available, download the firmware manually from the official Xiaomi website (select the Redmi Note 9 model, Global region or the official Xiaomi website). EEA).

To reset settings (without data loss):

1. Open Settings → About the phone → Reset settings.
2. Choose Reset all settings (not to be confused with Reset to factory!).
3. Confirm the action and restart the device.

⚠️ Note: If after the update MIUI The card is no longer defined, this may be due to a change in security policy. MIUI 13) Xiaomi has tightened control over external media. Try to roll back to the previous version via Fastboot or use Magisk to bypass restrictions (requires an unlocked bootloader).

6. Alternative methods: debugging by USB and ADB

For power users who aren’t afraid of the command line, there are diagnostic methods through ADB (Android Debug Bridge) which will help if the map is defined by the system but not displayed in the interface.

Instructions:

1. Turn on Developer Mode: Go to Settings → About Phone and tap the MIUI version 7 times.
2. Return to Settings → Additional → For developers and activate Debugging over USB.
3. Connect your phone to your PC, open Command Prompt and type: adb shell sm list-disks If the card is identified, you will see its identifier (e.g., disk:179.64).
4. To install the card manually, use: sm mount -o rw -f vfat /dev/block/mmcblk1p1 /storage/XXXX-XXXX (substitute mmcblk1p1 and the way to relevant to your system).

If sm commands don’t work, try an alternative method using mount:

su


mount -o remount,rw /dev/block/vold/public:179_64 /mnt/media_rw/XXXX-XXXX

⚠️ Attention: use ADB It requires root rights or unlocked bootloaders, wrong commands can lead to data loss or system failure.

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If SD-map is determined ADB, but not visible in MIUI, The problem lies in the Storage Access Framework, solution: clear the cache and data of the Storage application (com.android.externalstorage) through the settings.

FAQ: Frequent questions about SD-maps in Redmi Note 9