Modern devices Samsung Galaxy often lack a memory card slot, but many mid-range and budget segment models still support storage expansion. When the built-in memory fills up with photos, videos or heavy applications, an external drive comes to the rescue. However, before first use or if reading errors occur, the system requires a media preparation procedure.
The process formatting completely clears the drive, deleting all existing data and creating a new file structure that is understandable to the operating system Android. This is a critical step to ensure stable operation of the device and prevent future loss of information. Ignoring this step may result in the phone simply not seeing the connected flash drive.
In this article we will look in detail at how to correctly perform this procedure on smartphones Samsung with a shell One UI. We'll look at the choice between portable storage and internal memory, talk about file systems, and answer common questions that users have when working with external drives.
Preparing equipment and checking compatibility
Before you start setting up, you need to make sure that your equipment is physically compatible. Not all models Samsung have a connector microSD, so to connect a regular USB flash drive you will need a special adapter. For modern models with a port Type-C you need an appropriate OTG adapterthat converts the connection interface.
Make sure that the drive itself is working. Try connecting it to your computer to check the readability of the data. If the flash drive is detected on the PC but not visible on the phone, the problem almost certainly lies in the file system or the need for formatting. It is important to understand that the preparation process will destroy all files, so save important documents in advance.
⚠️ Attention: Make sure that the smartphone battery level is at least 30-40%. A sudden power outage while writing system tables can lead to logical damage to the drive, after which it will no longer be detected by any devices.
It is also worth checking the version of the operating system. Although the basic functionality of working with USB is the same on all versions Android, the location of the menu in the shell One UI may vary slightly depending on the year of manufacture of the model. Current firmware provides better support for new generation file systems, such as exFAT.
Use only certified OTG cables. Cheap analogues may not provide sufficient current to operate energy-intensive flash drives, which will lead to constant drive shutdowns.
Connecting the drive and initial diagnostics
After you insert the flash drive into the adapter and connect it to your smartphone, the system should respond instantly. In most cases, a system message about connecting a new USB device appears at the top of the screen (“notification shade”). If there is no notification, try reconnecting the cable or checking the connector for dust.
To get started, go to the main device settings. Find the section Device Maintenance or immediately open the item Storage. In the list of available drives, in addition to the internal memory, your external drive should be displayed, often marked “USB drive” or the name of the flash drive brand. If an error or "Not Supported" status is displayed instead of the name, formatting is required.
Click on the name of the connected drive. The system will offer several options for action. This is usually configured as portable storage or used as internal storage. The choice depends on your goals: do you just want to upload files or do you plan to install applications directly onto the flash drive.
Selecting a mode of use: Portable or Internal
This is the most important step that determines the future fate of your drive. Samsung, like other manufacturers, offers two fundamentally different ways to use external memory. Understanding the difference between them will help you avoid disappointment in the future.
Mode Portable storage (Portable Storage) is the standard and most secure option. In this mode, the flash drive works like a regular external drive. You can freely remove it and connect it to your computer, TV or other phone without losing data. However, you cannot install applications on such a drive - it is only used for media files and documents.
The second option is Internal memory (Internal Storage). This feature, known as Adoptable Storage, encrypts the flash drive and merges it with the system partition of the phone.
- 🔒 The data is encrypted with the key of the specific phone, so the flash drive will not work on other devices.
- 📱 You can transfer heavy applications and games to an external drive, freeing up place in the system.
- ⚡ The speed of the flash drive becomes critical: a slow drive will slow down the operation of the entire smartphone.
⚠️ Attention: When selecting the “Internal Memory” mode, the flash drive will be formatted in a specific way. You can return it to its normal state only by reformatting it, which will again delete all data. Don't choose this mode for cheap and slow memory cards.
If you're not sure of your needs, start with portable storage mode. This gives you the flexibility to test the speed of your drive without the risk of tying it to one device forever. At any time, you can change the purpose of the disk in the storage settings.
Why may the "Internal Memory" button be inactive?
The manufacturer may programmatically limit this function on some models. In addition, the system automatically blocks this mode if it detects that the drive's write speed is too low for comfortable operation of applications.
Step-by-step guide for formatting
When the mode is selected, the system will automatically prompt you to format the disk. If the automatic suggestion does not appear, this can be done manually through the settings menu. The procedure takes from a few seconds to a couple of minutes, depending on the volume of the drive.
To manually start, follow the path Settings → Device maintenance → Storage. Find your flash drive in the list and click on the three dots in the corner or on the name itself to open an additional menu. Select Storage settings or Format.
The system will issue a warning that all data will be deleted. Confirm the action by pressing the button Format or Erase and format. Do not remove the drive during this process. Upon completion, you will see a notification about successful preparation, and the flash drive will be available for writing files through the app My files.
☑️ Format checklist
After completing the procedure, it is recommended to restart your smartphone. This will allow the system to correctly remount the file system and make sure that all paths to the new storage are entered correctly. Now you can start transferring photos or installing apps.
Format through the smartphone settings is the only safe way to prepare a flash drive for working with Android, since the system itself selects the optimal cluster and file structure.
File systems: FAT32, exFAT and NTFS
When formatting on devices Samsung the user can rarely explicitly select a file system - the system does this automatically depending on the disk size. However, understanding the differences between them is useful for diagnosing compatibility problems.
For drives up to 32 GB, the system is most often used FAT32. It has maximum compatibility: such flash drives can be read by any TV, radio and computer. The main disadvantage is the inability to record one file larger than 4 GB, which is critical for storing movies in high quality.
For volumes over 32 GB, the standard is exFAT.
| Characteristics | FAT32 | exFAT | NTFS |
|---|---|---|---|
| Max. file size | 4 GB | Almost unlimited | Almost unlimited |
| Android compatibility | Full | Full | Read only (often) |
| TV compatibility | High | Average (new models) | Low |
| Reliability | High | Average | High (logging) |
The system NTFS is native to Windows, but has limited support on Android. Often phones can only read data from NTFS flash drives, but not write to them. If your flash drive is formatted in NTFS and the phone does not see it or prohibits writing, you need to reformat it to exFAT directly on the smartphone.
Eliminating errors and detection problems
Sometimes, even after a correct connection, the phone displays the message “USB drive is damaged” or simply ignores the device. Most often this is due to a software failure of the file system, which can be easily corrected by formatting. However, there are other reasons.
Try clearing the cache of the system application responsible for storing data. Go to Settings → Applications, find in the list (you may need to enable the display of system processes) application Storage or Media Storage. Click Memory and select Clear cache. After that, reconnect the flash drive.
If the problem persists, it may be due to physical damage to the contacts adapter or the phone port itself. Try gently cleaning the connector Type-C with a dry soft brush. Also check if the OTG adapter is overheating - some cheap models fail under prolonged load.
⚠️ Attention: If the system constantly reports damaged sectors immediately after formatting, the flash drive's resource is most likely exhausted. Using such a drive is dangerous - you can lose data at any time without the possibility of recovery.
In rare cases, enabling USB debugging mode helps, although this is rarely required for ordinary flash drives. Go to Settings → About phone → Software information and quickly click 7 times on Build number. Then in the menu that appears Developer options check the default USB configuration settings.
If The flash drive is detected, but the files are not copied, check the availability of free space not only on the drive, but also in the system’s temporary clipboard. Rebooting the phone often solves this problem.
Is it possible to format a flash drive without losing data?
No, this is not possible using standard Android tools. Formatting, by definition, involves creating a new file structure, which requires clearing out old content. To save data, you must first copy it to a computer or cloud storage.
Why does the phone not see a 128 GB flash drive?
Most likely, the flash drive is formatted into a file system that your phone does not support (for example, a specific Linux or Mac OS partition), or the drive requires external power that the phone port cannot provide. Try formatting it on your PC in exFAT.
Is it safe to remove a flash drive without the "Eject" button?
It is highly not recommended. Although modern phones have caching mechanisms, physical retrieval while writing can corrupt the file table. Always use the “Safely Remove” notification in the notification shade before disabling.
How to transfer applications to a formatted flash drive?
This is only possible if you have selected the “Internal memory” mode. In Portable Storage mode, application transfer is not available. To transfer, go to Settings → Applications, select the desired app and click “Change” if the button is active.
What to do if, after formatting, the flash drive has become smaller in volume?
Part of the volume is always reserved by the system for service tables and the file system structure. In addition, manufacturers indicate the full volume in the decimal system, and Android displays it in binary, which is why 32 GB turns into approximately 29 GB of available space.