In the latter half of last year, Xiaomi began locking the bootloader of its devices, to prevent third party sellers from bundling malware in their phones.
This however, annoyed users because Xiaomi imposed a rather ridiculous rule, which involved the user submitting a request to the company, for unlocking the bootloader manually.
And the fact that the company's approval process takes days, is an added pain. But fortunately you don't have to wait for days to unlock the device, if you follow a different process. This is an unofficial method but is perfectly safe too.
Androidpure and the author are not responsible for any damage you incur. Proceed at your own risk.
Unlocking the bootloader will completely erase all data and files on the internal storage. So please back up your photos, videos,, music, etc to your memory card, or better, to your PC before proceeding.
How to unlock the bootloader on the Redmi Note 3 instantly
1. First ensure that you have the correct model, i.e, the Redmi Note 3 powered by a Qualcomm Snapdragon 650, which is sold in India simply as the Remdi Note 3, and in other countries as the Redmi Note 3 Pro. This model is codenamed Kenzo and it is the one this guide is for. (Just FYI, the Mediatek variant is called Henessy).
2. Now, download this MIUI 7 Fastboot ROM to your computer and extract the TGZ file (which has a TAR file inside it) to another folder.
MD5 Checksum: 9706E1256126FCB74F373BCAB6848E9E
For the sake of convenience move the content of the 2nd folder to your desktop or any other location, and rename it to something shorter.
3. Download the Unlocked bootloader.zip which contains the modified bootloader. Extract the file inside it, copy and paste it to the images folder inside the fastboot ROM folder from step 2.
Xiaomi requires users to reply to the thread at its forums, to view the download link. We hate that, which is why we uploaded the file to AndroidPure's dev host account.
MD5 Checksum: F69EEB321FB63C4CCAC51CBEF7545B87
This replaces a file of the same name in the folder. For example if you extracted the fastboot ROM to your C drive's root directory, the file should be pasted in
4. Finally, download the Mi Flash Tool and save it to your PC.
To install all the drivers correctly, you need to Disable Driver Enforcement on your PC. This is because Xiaomi's drivers are not digitally signed. For Windows 10, you can do it by following the process below.
Press Windows + I to open the Settings app. Select Update and Recovery, and then click on Recovery in the left sidebar. The PC should restart, and once it does it will prompt you with various options.
Select Advanced Startup, and then it should give you a list of features which will be available upon next restart. Do so, and a screen will come with up with a list of boot options, hit the F7 or the Number 7 key on your keyboard, and your PC will boot into Windows 10 with Driver Enforcement Disabled.
Install the Mi Flash Tool, and click on "install driver anyway" when prompted by the Windows' pop-up warning.
5. On your Redmi Note 3, navigate to Settings > about phone and tap the MIUI Build number 7 times to unlock the Developer options.
6. Go back to the Additional Settings > Developer options, and enable OEM Unlock, and USB Debugging.
7. Connect your Redmi Note 3 to the PC via a USB cable.
8. Now, on your PC, navigate to the folder where the Mi Flash tool is installed. You need to open the Google folder which has the adb, and fastboot EXE files. This is usually located in C:\Program Files (x86)\Xiaomi\MiPhone\Google\Android.
9. Hold down the shift button and right click on an empty space in the folder. Select open command window here, and a command prompt terminal should open.
10. Type the following command in the window:
Your phone will prompt you to allow USB debugging for your computer. Allow it, and you should see an alpha-numerical code in the CMD window.
This means your phone is connected to the PC.
11. Type the following command in the window:
adb reboot edl
The device should reboot into the Emergency Download Mode. Your device's LED notification will be blinking, while the display will be off.
12. Open the Mi Flash Tool from C:\Program Files (x86)\Xiaomi\MiPhone
13. Click the Browse button and select the folder where you extracted the fastboot ROM to. (Refer step 2)
14. Click the Advanced button and set the following options.
a. first option = flashall.bat (it is in fastboot rom folder)
b. third option = prog_emmc_firehose_8976_ddr.mbn (in the images folder)
c. seventh option = rawprogram0.xml
d. eighth option = patch0.xml
15. Hit the X button to close the Advanced Window, and select refresh in the Mi Flash tool. You should now see the device listed in the UI as COM port # where the # represents some number assigned by your PC.
The device is listed as Qualcomm HS-USB QDLoader 9008 in the device manager.
16. Click on the Flash button in the Mi Flash tool, and it should begin installing the ROM with the modified bootloader.
Do NOT unplug the device from the PC. Wait for the tool to say the process was completed successfully.
17. Unplug the phone, and press the key combo Power + Volume Down for about 30 seconds till you feel the device vibrate. This will bring a Mi Bunny screen with the words Fastboot, meaning the device is in fastboot mode.
18. Plug the device to the USB Cable and switch to the CMD window on your PC, and type the following command.
fastboot oem device-info
This will show the bootloader information, which should read as false for the unlocked status.
19. Type the following command
fastboot oem unlock-go
This will unlock the bootloader and erase all the data on your phone's internal memory.
20. Type the following command to verify the bootloader status
fastboot oem device-info
It should now show the unlocked status as true.
Congratulations you have unlocked the bootloader of your Redmi Note 3. Now you can flash TWRP recovery and then install any custom ROM on it like Cyanogenmod 13 on your phone.
21. Type the following command to reboot the phone:
I used this method on my Redmi Note 3 which was running on MIUI 8 Global Beta to unlock its bootloader, so you can use it on any MIUI version.
source: MIUI Forums