How to Relock the Bootloader on Any OnePlus device

In this guide, we will show you how to relock the bootloader on your OnePlus devices. This guide is valid for all the OnePlus variants, running any Android and OxygenOS version. For the unaware, Bootloader is a software program that instructs the underlying OS which all apps do it needs to load during the boot-up time. Furthermore, it also helps in booting your device to Fastboot or Bootloader mode (remember the adb reboot bootloader command?). There are literally tons of advantages associated with an unlocked bootloader.

These include the ability to flash a custom recovery, most noticeably TWRP. Once we are in control of TWRP, there is a plethora of tweaks possible via it. For example, installing ZIP and IMG files, flashing the custom and GSI ROMs, and all become a cakewalk if done via TWRP. Likewise, the icing on the cake is the ability to take a backup of all the device partitions (including data) in the form of Nandroid Backup. And if you aren’t satisfied with it, you could even flash the Magisk ZIP installer and obtain administrative rights. Well, there are tons of other modifications possible.

But since you are reading this guide, most of you might already have an unlocked bootloader and would be aware of the associated perks as well. However, what many don’t seem to know is that with these goodies comes some uninvited risks too. More often than not, owing to these risks, many users wish to revert on their bootloader unlocking decision. If you have a OnePlus device and share similar thoughts as these users, then you have landed in the right place. Today we will show you how to relock the bootloader on any OnePlus device. But first, let’s check out the need to do so. After that, we will list out the detailed instructions set. Follow along.

The Need for a Locked Bootloader

There’s no denying the fact that an unlocked bootloader lets you welcome many new modifications to your device. Some of you might already have tried them onto your device. But everything is not so good in the first place. There are always two sides to the coin, and the same is the case here as well. To begin with, as soon as you unlock the bootloader, you might have to bid adieu to your device’s warranty. Furthermore, all the data will be wiped as well. Adding to it is the fact that an unlocked device is always more prone to security attacks than a locked device. Likewise, many OEMs don’t allow you to install official OTAs. So you might be missing on new features and stability improvements.

Many apps also fail to work with an unlocked device. Google Pay and Pokemon Go are two famous apps in this domain. Similarly in apps like Netflix, you could no longer watch content in HD as you will lose the Widevine L1 Certificate and will be degraded to L3. Not to mention that there are always some associated risks in the form of the device getting bricked or in a bootloop. To counter all these issues, there is a simple solution at hand- to lock the bootloader of your device. And in this guide, we will be listing the instructions for just that. So without further ado let’s begin with the tutorial on how to relock the bootloader of any OnePlus device.

Relock the Bootloader on OnePlus devices

To begin with, there are some pretty important requirements that your device needs to qualify. Make sure to go through each of them before proceeding with the steps. Here they are:

Prerequisites

• First and foremost, your device shouldn’t be tweaked with. That is, it should be having the stock recovery, stock OxygenOS, no mods, and it should not be rooted. So TWRP, magisk, and Custom ROMs is a big no. Make sure you revert to the stock ROM and unroot your device before proceeding with the steps. If there is even a slightest of modifications with your device, we would advise you not to proceed ahead. This is because you will surely end up with a bricked device. So go and remove every little bits and piece of modifications from your device. When that is done, move over to the next point.
• Next up, create a complete backup of your Android device. This is because relocking the bootloader will wipe off all the data from your device.
• Also, download and install the latest OnePlus USB Drivers on your PC.
• You will also have to enable USB Debugging to enable the execution of ADB Commands. So head over to Settings on your OnePlus device. Then navigate to Build Number and tap on About Phone 7 times. Go back to Settings > System > Advanced > Developer Options. Now enable the USB Debugging toggle.
  
• Finally, install the Android SDK and Platform Tools on your PC. This is needed so that your PC recognizes your device in ADB and Fastboot modes.

That’s all from this section. You could now proceed with the instructions to relock the bootloader on your OnePlus device.

Steps to Relock Bootloader on OnePlus

1. Connect your OnePlus device to PC via USB cable. Make sure it is free of all modifications and USB Debugging is enabled.
2. Now head over to the platform-tools folder, type in CMD in its address bar, and hit Enter. This will launch the Command Prompt window.
3. Next, enter the below command to boot your device to Bootloader/Fastboot mode.

   adb reboot bootloader

   

4. Now type in the next command to verify the fastboot connection. If you get an alphanumeric string along with the fastboot text, then the connection has been successfully established:

   fastboot devices

   

5. Finally, enter the below command to relock the bootloader of your OnePlus device. As already mentioned, executing the below command will reset your device:

   fastboot oem lock

6. In this stage, you will get a confirmation message on your device. use the Volume keys to highlight the “Yes, Lock Bootloader” option and hit the Power button to confirm your decision.
   
7. That is it. With this, you have successfully relocked the bootloader. Your device should now boot to the Android OS. If by any chance it is still in fastboot, then use the below command to boot it to the system:

   fastboot reboot

So this was all from this guide on how to relock the bootloader on your OnePlus device. The first boot after carrying out this process might take a little bit more time, nothing to worry about. Similarly, once your device boots, you will have to sign in to your Google account to bring back the data (as the device would have been reset). On that note, if you have queries concerning the aforementioned steps, the comments section is all yours. Rounding off, here are some iPhone Tips and Tricks, PC tips and tricks, and Android Tips and Trick that you deserve your attention as well.