Bootloader unlocking on Xiaomi Redmi 9C NFC is a procedure that opens up access to advanced smartphone features such as custom firmware installation, root rights or device recovery after software failures. However, Xiaomi’s standard method involves a complete data reset, making it unacceptable for users who store important information. In this article, we will discuss legal and alternative ways to unlock without losing files, as well as assess the risks and nuances of the process.
The Redmi 9C NFC (codename angelicanfc) is a low-end model, but its MediaTek Helio G35-based hardware platform and MIUI firmware place restrictions on how to manipulate the bootloader. It is important to understand that no method has a 100% guarantee of data retention - there is always a risk of critical failure. So, before starting the procedure, it is recommended to back up through Settings → Additional → Backup and Reset or third-party utils like Titanium Backup (requires).
In the article, we will look at:
- 🔓 Official way to unlock through Mi Unlock Tool and its limitations
- 🛠️ Alternative methods using fastboot and ADB
- ⚠️ Risks to Data and How to Minimize Them
- 🔧 Necessary tools and device preparation
- 📱 Features of the Redmi firmware 9C NFC Compatibility with custom recavers
Why Xiaomi is blocking the bootloader and can it be unlocked without resetting?
Xiaomi is blocking the bootloader on all its devices for two key reasons: security and ecosystem control.
- 🔒 Unauthorized access to data during theft (without unlocking it is impossible to reset the pattern lock via fastboot)
- 🦠 Malware installations at the firmware level
- 📉 Disturbances of stability due to incompatible modifications
The official Mi Unlock Tool requires a Mi Account and a mandatory data reset (fastboot oem unlock), which is due to the anti-rollback mechanism, which can lead to a device “brick” if you do not act correctly. However, there are workarounds that allow you to save user data when you unlock, but they require a deep understanding of the processes and do not guarantee success at 100%.
Important: On the Redmi 9C NFC with MediaTek, unlocking is complicated by the lack of official EDL-enabled unlocking support (as on Qualcomm devices), which narrows the list of available methods.
Preparation of the device: what to do before unlocking
Before you start unlocking, follow the mandatory preparatory steps, which can lead to loss of data or inability to restore the device.
Battery charge ≥ 70% | Backup of important data | ADB/Fastboot drivers installed on PC | OEM lock disabled in developer settings | Firmware compatibility checked with unlock-->
Detailed instructions for preparation:
- Activate Developer Mode: Go to Settings → About Phone → MIUI Version and press 7 times on this item. The Developer section will appear in the menu.
- Allow debugging over USB: in Settings → Additional → For developers, enable USB Debugging and OEM Unlocking.
- Link your Mi Account: in Settings → Mi Account log in and wait for sync (can take up to 72 hours).
- Check the bootloader status: turn off the phone, press Power + Volume down to log in to fastboot. Connect to the PC and execute the command: fastboot oem device-info If the answer Device unlocked: false - the bootloader is blocked.
For Redmi. 9C NFC It is critical to use the original USB-cable (not all cables support fastboot data transfer) and also make sure that the PC has MediaTek Preloader drivers – without them, the device will not be determined in unlock mode.
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If the fastboot oem device-info command returns an error, try reinstalling drivers via the Mi Flash Tool or using USB 2.0 ports (USB 3.0 sometimes conflicts with the fastboot protocol).
The official method of unlocking through Mi Unlock Tool
The standard way Xiaomi uses the Mi Unlock Tool, but it is guaranteed to erase all data from the device.However, it should be considered as a basic option, since alternative methods may not work on new versions of MIUI.
Step-by-step:
- Download Mi Unlock Tool (the version should match the region of your Mi Account).
- Launch the utility on behalf of the administrator and log in under the same account as on the phone.
- Turn Redmi 9C NFC into fastboot (Power + Volume down) mode.
- Connect the device to the PC. Press Unlock in the utility.
- Confirm the agreement and wait until the process is completed (usually 10-15 minutes).
Once unlocked, the phone will automatically reset to factory settings, and it will be impossible to recover data after that unless a backup has been created.
What to do if Mi Unlock Tool gives you a "Couldn't unlock" error
Alternative Unlocking Methods Without Losing Data
There are informal ways to unlock a bootloader without resetting, but they require advanced skills and carry risks. Below are two of the most workable methods for the Redmi 9C NFC.
Method 1: Use of a vulnerability in fastboot (only for older versions of MIUI)
This method is based on an exploit that allows you to bypass the reset check. It works on MIUI firmware 12.0.2 and below:
- Download a modified fastboot from XDA Developers (e.g. FastbootEnhanced).
- Transfer the phone to fastboot mode and connect to the PC.
- Follow the command: fastboot oem unlock_bypass 123456 (where 123456 — arbitrary code that does not affect the result).
- If the command is error-free, run the standard unlock: fastboot flashing unlock
⚠️ Attention: On new versions MIUI This method can lead to a soft brik (the device only loads in fastboot). SP Flash Tool with data loss.
Method 2: Unlocking through temporary root (Magisk)
If the device already has Magisk installed (for example, through the boot.img patch), you can try unlocking the bootloader without resetting:
- Install Magisk module with support for fastboot commands.
- At the Magisk terminal, perform: su echo 1 > /proc/sys/kernel/oem_unlock_allowed
- Reboot to fastboot and execute the standard unlock command.
This method does not work on all devices and may require additional manipulation of vbmeta files.
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Alternative unlocking methods without losing data do not guarantee success and can lead to unstable operation of the device.
Risks and Possible Problems in Unblocking
Unlocking the bootloader is a procedure with consequences. Even if you successfully complete it, you may encounter:
| Problem. | Reason. | Decision |
|---|---|---|
| Loss of data | Resetting on official unlocking or failure in an alternative method | Restore from backup (if created) |
| Brick of the device | Incompatible firmware or interrupted process | Firmware via SP Flash Tool in Download Only mode |
| Denial of warranty service | Unlocked bootloader cancels warranty | Closing the loader before contacting the service center |
| Problems with OTA-update | MIUI blocks updates on unlocked devices | Manually Install Updates via fastboot or TWRP |
On Redmi 9C NFC, pay special attention to anti-rollback protection. If you roll back to an older version of MIUI after unlocking, the device may stop turning on. Check the current firmware version in Settings → About Phone → MIUI version and compare it to supported versions on the XDA or 4PDA forums.
⚠️ Warning: If the phone stopped booting after unlocking, don't try to flash it through the Mi Flash Tool with the Clean All option - this will permanently delete the data. Use Download Only and select the firmware with the same version MIUI, previously established.
What to do after successful unblocking
Once the bootloader is unlocked, your Redmi 9C NFC is ready to install custom firmware or Recovery, but before further manipulation:
- 🔄 Update your firmware to the latest stable version via fastboot to avoid conflicts.
- 🛡️ Install. TWRP (If you are planning to use custom firmware. - For Redmi 9C NFC fitting TWRP 3.5.2 from the official website.
- 🔐 Create a full backup through TWRP (boot, system, data sections).
- 📱 Check the performance of the main functions: cameras, NFC, sensor.
To install TWRP on Redmi 9C NFC, use the command:
fastboot flash recovery twrp-3.5.2_angelicanfc.img
fastboot boot twrp-3.5.2_angelicanfc.imgAfter first logging into TWRP, be sure to execute Format Data (if required for encryption) and reboot to the Recovery, not the system.
If you unlock the bootloader to get root rights, install Magisk via TWRP:
- Download the latest Magisk.zip from GitHub.
- In TWRP, select Install and specify the path to the archive.
- After installation, restart.
⚠️ Attention: MIUI 13+ for Redmi 9C NFC You may need to disable dm-verity via Magisk (MagiskHide Props Config) module, otherwise the system will restart in fastboot.