How to insert a flash drive into the phone Xiaomi Redmi 9: 3 proven ways + problem solving

Xiaomi Redmi 9 — One of the most popular budget smartphones, but many users are faced with the question: how to connect a flash drive to it? USB-Type C port with support OTG "Out of the box, the microSD slot is often busy. SIM-In this article, we'll look at all the working ways of connecting. USB-storage devices and memory cards, including nuances with formats FAT32/exFAT, Selection of adapters and solution of typical errors.

It's important to understand that Redmi 9 supports OTG (USB On-The-Go), but it requires the right adapter. We tested 5 different adapters and found out which ones work consistently and which cause problems with power or reading speed, and you will learn how to set up automatic mounting of the USB drive in MIUI, why the phone may not see the drive, and what to do if the files on the flash drive do not open.

This article is relevant for all Redmi 9 modifications (including Redmi 9A, 9C, 9T) and MIUI 12-14 firmware. If you have another Xiaomi model, check the compatibility of OTG in the characteristics of the device.

1. Which flash drives are compatible with Xiaomi Redmi 9

Before you buy an adapter, make sure your drive is suitable for working with a smartphone.Redmi 9 supports:

• 📁 USB-flash drives (format) USB 2.0/3.0) capacity 256 GB (tested on SanDisk Ultra, Kingston DataTraveler)
• 📱 MicroSD cards (up to 512 GB, class) UHS-I Class 10 – via a slot or adapter
• 💾 External HDD/SSD separate power (drives without power may not be determined)

An important nuance: the phone does not work with flash drives formatted in NTFS.

If your USB flash drive is formatted in NTFS, reformat it via your computer (instructions in section 5). Also note that the read/write speed on USB 2.0 (via OTG) will be lower than on USB 3.0 – an average of 10-20 MB/s versus 40-60 MB/s.

⚠️ Note: Some cheap flash drives (especially "no-name") may not be identified due to poor controller quality.

2. Method 1: Connecting through OTG-adapter (USB-A → USB-C)

The most universal method is to use OTG-plug-in USB-C (male on the side of the telephone and USB-A (Female) for flash drives. USB-accumulator.

Step-by-step:

1. Buy a certified OTG-Adapter (we recommend Anker or Baseus – they provide stable power supply).
2. Insert the adapter into the USB-C connector of the phone (connection order is important!).
3. Connect the flash drive to the adapter. A notification will appear on the screen "USB-drive-in".
4. Slip on the notification and select "Open" or "Use as a media device".

If the notification does not appear:

• 🔄 Reconnect the flash drive (sometimes helps to remove and insert again).
• 🔋 Check the phone’s charge at a level below 15% OTG may not work.
• ⚙️ Go to Settings. → Connected devices → USB and select the "File Transfer" mode".

Check the compatibility of the flash drive (FAT32/exFAT)

Charge your phone to at least 20%

Use the original. OTG-adapter

Update. MIUI last-minute-->

The speed depends on the quality of the adapter. In our tests, cheap Chinese adapters (~$1) showed a read speed of 5-8 MB / s, while Anker PowerExpand gave 18-22 MB / s.

The original Xiaomi

Baseus/Anker

Cheap no-name

I'm not plugging in the flash drives.-->

3. Method 2: Using a card reader for a microSD

If you have a microSD card, but the slot in your phone is busy SIM-card, you can use an external card reader with an interface USB-C or USB-A (through OTG). This method is suitable for flash drives up to 512 GB.

How to connect:

1. Insert the microSD into a card reader (e.g., SanDisk MobileMate).
2. Connect the card reader to the phone through OTG-adapter (if the card reader has a connector) USB-A).
3. Wait for the notice "SD-Card connected and open files via "Conductor".

Advantages of the method:

• 🔄 You can quickly change memory cards without retrieving them. SIM.
• 📱 High-speed maps are supported UHS-I (up to 90 MB/s of reading).
• 💰 Cartridgers are cheaper OTG-adapter USB-flash-drive.

⚠️ Attention: Some card readers require additional power. If the phone gives an error "Device not recognized", try connecting the card reader to charge via the device. USB-hub.

Method 3: Connecting via a wireless adapter (Wi-Fi)

If you don't. OTG-Adapter, you can use wireless USB-Adapter (e.g. TP-Link) TL-WN725N It's slower (speed is limited by Wi-Fi) but doesn't require a physical connection.

Instructions:

1. Connect the flash drive to the wireless adapter and turn it on.
2. On your phone, connect to the adapter's Wi-Fi network (usually the network name is "SanDisk-XXXX" or "TP-Link_XXXX").
3. Open your browser and enter the adapter address (e.g. 192.168.1.1 or sandisk.local).
4. Download the files you want or use an official app (such as SanDisk Memory Zone).

Cons of the method:

• ⚡ The data transfer speed is 2-3 times lower than the data transfer speed OTG (3-5 MB/s).
• 🔋 Adapter drains phone battery faster (Wi-Fi module consumes) ~200 m).
• 📶 Requires a stable connection – with a weak signal, files can be damaged.

This method is convenient for one-time copying of large files (for example, movies or backups), but is not suitable for permanent use.

💡

If the adapter is not detected, try turning off battery saving for the Wi-Fi Settings app in Settings → Battery → Charge Savings.

5. How to format a flash drive for Xiaomi Redmi 9

If the phone doesn't see the flash drive, the first reason is the wrong file system. Redmi 9 doesn't support NTFS, so the drive needs to be reformatted to FAT32 or exFAT.

Instructions for Windows:

1. Connect the flash drive to the computer.
2. Open "This Computer", right-click on the flash drive and select "Format".
3. Select the file system: For flash drives up to 32 GB, FAT32. For flash drives up to 64-256 GB, exFAT.

"Start."

For macOS, use the Disk Utility (Applications → Utility) by selecting the GUID scheme and exFAT format.

⚠️ Attention: Formatting deletes all data! If there are important files on the flash drive, copy them to your computer first. Also avoid formatting quickly - it can leave errors.

Important: Drives with a capacity of more than 256 GB may not be detected even after formatting in exFAT. This is a restriction of the MIUI firmware - in this case, use a microSD card or external powered HDD.

6. Solving typical problems

Let’s look at the most common mistakes and ways to eliminate them:

If none of these methods helped, check:

• 🔌 Port port USB-C phone for physical damage (dust, pollution).
• 📱 Version MIUI — In the old firmware (below 12.0.3) were bugs with OTG.
• 🔄 Developer Mode: Enable Debugging by USB In Settings → The phone. → Version. MIUI (tap 7 times).

💡

If the flash drive is detected, but the files are copied very slowly (<5 MB/s, the problem is probably cheap OTG-Replace it with a support model. USB 3.0 (For example, Anker. 310).

7. Alternative methods of file transfer

If you can’t connect the flash drive, consider alternatives:

• ☁️ Cloud storage (Google Drive, Mi Cloud, Yandex Disk) – convenient for small files.
• 📶 FTP-server FX File Explorer or Solid Explorer (allows you to transfer files over a local network).
• 🔗 Direct link via Telegram (send the file to yourself in "Saved Messages").
• 📡 Bluetooth/Wi-Fi Direct – Slowly but without the internet.

For larger files (>1 GB), it is better to use a local area network:

1. Install Xender or Send Anywhere on your phone and computer.
2. Connect both devices to the same Wi-Fi network.
3. Send files via the application (speed up to 10 MB/s).

If you need to work with large amounts of data on a regular basis, consider buying an external SSD with an OTG (such as the Samsung T7 Shield), which supports USB 3.2 and speeds up to 1000 MB/s, but requires a powered adapter.

FAQ: Frequent questions