How to allow access SD-Xiaomi Redmi Note 9 map: all ways + mistake-making

Owners of Xiaomi Redmi Note 9 often face a problem: the smartphone does not see SD-It's a card or it's blocking file recordings, even though the media is physically sound, and it's because of security policy. MIUI, This is a default that restricts applications from accessing external memory. In this article, we will discuss 5 working ways to unlock access, from basic settings to hidden features for power users.

The Redmi Note 9 (M2003J15SC/M2003J15SS) features microSD support of up to 512 GB in a hybrid slot (instead of the second SIM).

• 🚫 «SD-map not detected" - physical problem or incorrect format;
• 🔒 «No access to the folder – restrictions MIUI recorded;
• ⚠️ «Read-only map – locking the file system;
• 📱 «Application cannot save files – no permissions.

Before you start settings, make sure the card is formatted in FAT32/exFAT (for cards >32 GB) and is not damaged. If the smartphone does not recognize the media at all, check it on another device or through a card reader.

1. Allow access through MIUI settings

The easiest way is to include read/write rights in the MIUI menu, which works for all firmware versions (from MIUI 12 to MIUI 14) and does not require root rights.

Instructions:

1. Open the Settings → Memory.
2. Tap your name on it. SD-maps (e.g. SanDisk) 128GB).
3. In the top right corner, press ⋮ → Storage settings.
4. Activate the switch as internal memory (if you need full control) or use as a portable device (for limited access).
5. Confirm the action and wait until the process is completed (may take up to 5 minutes).

⚠️ Warning: Formatting as internal memory erases all data from the card and encrypts it for your Xiaomi account.

2. Set up permissions for individual applications

If SD-The card is visible in the system, but specific programs (for example, a gallery, camera or file bootloader) can not save data, you need to manually issue them the rights.

How to do this:

1. Go to Settings → Applications → Application Management.
2. Select the application you want (such as the camera).
3. Slip the Permits. → Memory.
4. Enable the Storage Switches and Manage all files (if any).
5. For some applications (for example, Google Photos) you additionally need to specify their settings SD-map.

💡 Useful tip: If the Manage all files section is missing, update the firmware to MIUI 13+ Use an alternative file manager (e.g. Solid Explorer).

💡

After issuing permissions, restart your smartphone - this will help to avoid failures when you first save files on your phone. SD-map.

3. Correction of the error "Read only"

If SD-The card is detected, but it gives an error "Disk is protected from recording", the problem may be in the:

• 🔐 Physical blocker on the adapter (check the slider on the side);
• 🖥️ File system (NTFS It is not supported on Android without root);
• 🛠️ Damaged sectors (you need to check on PC via chkdsk).

Decisions:

1. Reformat the card to FAT32 (up to 32 GB) or exFAT (over 32 GB) via PC.
2. If the card was previously used as internal memory, reset: → Memory. → SD-map → ⋮ → Formatting as a portable
3. For the Redmi Note 9 with root rights, you can remove the protection flag by the command: adb shell sm set-force-adoptable true (requires enabled USB debugging).

4. Reset access settings (if the card "disappeared" after the update)

After updating MIUI (particularly 12 on 13/14) Some users are losing access to SD-It's about resetting security policy to get access back:

Method 1: Reset the storage settings

1. Go to Settings. → Memory.
2. Tap it on. SD-map → ⋮ → Storage settings.
3. Select Disable (if the card is connected as internal).
4. Remove and re-insert the card – the system will suggest configuring it again.

Method 2: Cleaning up the Media Storage cache

1. Open Settings → Applications → Application Management.
2. Tap. ⋮ → Showing System Processes.
3. Find Media Storage → Storage → Clear the cache.
4. Reboot the phone.

💡

If SD-The map has ceased to be determined after the update MIUI, 90% of the time, it helps to reset its settings through the Memory menu».

5. Alternative methods for experienced users

If the standard methods did not help, try:

Method 1: ADB-teams (without root)

Connect your phone to a PC with USB Debugging enabled and do:

adb shell sm set-force-adoptable true


adb shell sm partition disk:179,64 private

Replace. 179,64 to the current parameters of your card (you can find out through adb shell ls) /dev/block).

Method 2: Edit platform.xml (requires root)

Open /system/etc/permissions/platform.xml in the root-access editor and add a line:

<permission name="android.permission.WRITE_EXTERNAL_STORAGE" />

sectionally <group gid="media_rw" />.

⚠️ Warning: Incorrect editing of system files can result in loss of warranty or device "brick!

Frequent mistakes and their solutions

FAQ: Answers to popular questions