Modern Xiaomi smartphones have a wide range of customization capabilities, but access to hidden system functions requires activation of special modes. One of the key settings that advanced users often look for is the OEM unlock option, which serves as a fundamental element of Android security, preventing unauthorized replacement of system software by attackers.
Many device owners face this setup when trying to get superuser rights or install custom firmware. Without understanding why Xiaomi OEM unlocks, you can get confused in the Developer Menu or worse, block access to important features. In this article, we will discuss in detail the purpose of this parameter, its impact on the Mi Flash Tool and the consequences of inclusion.
It's worth noting that activating this setting is not necessary for normal smartphone use. If you're just using your phone for calls, social media and photos, you don't have to interfere with these settings. However, for modding enthusiasts, this is the first step to full control of the device.
What is OEM Unlocking in Android
The term OEM (Original Equipment Manufacturer) in the context of the Android operating system refers to a specific security flag. Essentially, it is a switch that allows the bootloader to receive and run code that is not signed with the manufacturer's digital certificates. In the standard state, the phone checks the digital signature of each program being launched, including the system kernel.
When the function is turned off, the bootloader blocks the launch of any unofficial software, which creates a strong barrier against malware that tries to penetrate the deep level of the system, enabling the option removes this barrier, allowing you to replace the standard bootloader with a modified one, for example, TWRP or OrangeFox.
⚠️ Attention: Inclusion OEM Unlocking reduces the security of the device, and in theory, if an attacker gains physical access to the phone, they can replace the system partitions with their own.
It is important to understand the difference between unlocking a bootloader through Mi Unlock and turning on a toggle in the settings. The first step is the resolution from Xiaomi servers, and the second is the local resolution on the device itself, both steps necessary for successful flashing.
Technical details of the work of Bootloader
The bootloader is a small program that runs to the operating system. It initializes the hardware and transfers control to the Android kernel. The OEM lock is a digital signature check of that kernel. If the signature doesn't match the manufacturer's key, the download is blocked.> Why does the average user need this feature.For the vast majority of owners of Redmi and POCO smartphones, this setting will remain hidden and unnecessary. However, there are scenarios where even an inexperienced user may face the need to use it. First of all, it is to restore the device after critical errors, when standard reset methods do not work. If you plan to sell your smartphone, it is recommended to reset, reset it back to the factory. This will increase the buyer's confidence and ensure that the device has not been modified by third parties. OEM It may also be required for certain debugging and diagnostic tools that require deep access to the file system. Some enterprise applications or specific software for developers can check the status of the bootloader and refuse to work if it is unlocked. OEM Unlocking is the acquisition of superuser rights (Root). Without an unlocked bootloader, you can not install the modified recovery, which, in turn, is necessary for implementing rights management files such as Magisk or Magisk. SU. The process of installing custom firmware, such as Xiaomi.eu or LineageOS, is also impossible without this step. Custom recavers allow you to create full system backups (Nandroid backup), clean partitions clean and install software from the system. ZIP-archives that are not available in the stockpile mode. 🔓 Allows you to install modified versions of Android with advanced functionality. 🛠 It allows you to remove system applications that cannot be disabled by standard methods. ⚡️ It opens access to overclocking the processor and fine-tuning power consumption. It is worth noting that after unlocking the bootloader, some banking applications may stop working or restrict functionality due to the operation of SafetyNet or Play Integrity protection. API. While there are methods to circumvent this protection, it requires additional effort and knowledge. ☑️ What you need for a successful firmware Mi Account with more binding 7 Installed Mi Unlock Tool on PCIncluded OEM Unlocking in the developer menu Battery Charge More 50%Completed: 0 / 4 How to turn it on OEM The activation of this feature does not require a connection to the computer and is performed directly in the interface of the smartphone. However, to see the desired menu item, you must first activate the developer mode. Without this, the hidden settings will remain inaccessible to the user. The first step is to go to the About menu. MIUI» or "Version" OS» And press it fast. 7-10 Once in a row, the system will then notify you that the developer mode is activated, and now a new section "Additional" or "Extended settings" will appear in the main settings menu». Inside the Developer menu, you should scroll down to the Debugging block, and there you will find the Factory Unlock switch» (OEM Unlocking. Activation of this slider will require validation and input of the password or pattern lock of the lock screen -> The phone -> (We use tapa 7 times according to version MIUI) -> Additional settings -> For developers -> If the "Factory Unlocking" item is displayed in gray and not pressed, this may mean that the operator or manufacturer has blocked this possibility at the firmware level. In rare cases, you need an Internet connection to check the status of the device on the servers. ADB and Fastboot Debugging Mode by USB and OEM Unlocking is often mentioned together, but they perform different functions. ADB (Android Debug Bridge allows you to control your phone from your computer, transfer files and execute commands while the operating system is running. OEM Unlocking also affects the Fastboot mode, which runs before Android boots. To execute commands in Fastboot mode, such as fastboot flash or fastboot oem unlock, having the option enabled in the system is critical. Without it, teams will return the error "device unauthorized" or "command not allowed" -- this is protection against accidental damage to the device by connecting to someone else's PC. ADB Mode Fastboot Mode Requires Android enabled Yes No Need OEM Unlock No Yes (for recording) Use Debugging, Logs, Firmware Files, Unlock BL When working with tools like the Mi Flash Tool in Clean All mode, having an unlocked bootloader is a must. If you try to re-interview a device with a locked OEM, The process will end in an error at the signature verification stage. 💡Use the original. USB-cable USB 2.0 on the PC motherboard to avoid connection errors in Fastboot mode.The risks and consequences of unlocking It should be understood that the removal of restrictions OEM In the event of a non-software breakdown, the service center may refuse to repair free of charge, citing interference with the software part. In addition, the unlocked bootloader makes the device vulnerable to Evil Maid attacks, where an attacker can physically access the phone and install spyware when the screen is off. Also, features that require a high degree of trust, such as Google Pay (in some implementations) or banking applications with a hard-to-check environment, stop working. ⚠️ Warning: Once the bootloader is unlocked, the Mi Cloud function may not work properly or be completely disabled by the manufacturer for security reasons. This is a security measure to prevent the new owner from gaining access to the previous one's data, so make sure to back up important information before you start any manipulations. 📉 Reducing the overall security of personal data on the device. 🚫 Possible problems with work DRM-Content (Netflix in low quality). 🔄 Re-unblocking after each complete flashing. 💡Unlocking OEM — This is the point of no return for warranty service and the level of security of stock firmware. Frequent errors and how to solve them Users often face a situation where the menu item OEM There is no unlocking at all. In the new versions of HyperOS and MIUI 14 developers sometimes hide this option or change its location, check if Full Protection or similar security features are enabled, and another common problem is the Unable to Check error when you try to activate. This indicates problems with the network connection or Xiaomi servers. Try switching from Wi-Fi to mobile Internet or vice versa, and also check the correct set of date and time. If after turning on the option, the phone goes into an endless restart (bootloop), most likely, system files were damaged or the previously installed software conflicts. In this case, the only thing that helps is to flash through the Fastboot and clean the data completely. OEM If you try to lock the bootloader back on a device with custom firmware installed, the phone will go into the bootloop. The bootloader will check the signature, will not find the original one. MIUI You can only get it back through Fastboot mode and the stock firmware installation. Does it unlock when you reset? No, just resetting it to the factory settings (Wipe Data) from the phone menu doesn't lock the bootloader back. The unlock status is stored in a separate secure partition, so to return the lock, you need to execute a special command via Fastboot or use the official Mi Unlock utility in lock mode. OTA unlocked OEM? You can get updates over the air, but only if you haven't changed the system partitions. If you've installed custom firmware or modified the system partition, automatic updates will cause an error or loss of Root rights. In such cases, you need to install the firmware manually. Does this affect Widevine? L1? On most modern Xiaomi devices, unlocking the bootloader leads to a drop in the protection level of Widevine with the help of the device. L1 before L3. This means that streaming services (Netflix, Disney)+) They will only broadcast videos in low resolution (SD 480p), Even if the screen supports 4K.