How to Re-lock bootloader of any Android Smartphones


Unlocking bootloader opens the gate for you to explore many things in your smartphone. You can install TWRP , root your device, take a complete backup and restore it t any time. Here we’ve seen on how to unlock bootloader on any smartphones. But if you decided to re-lock your smartphone’s bootloader, it is very simple. Here let us see how to re-lock bootloader in any Android smartphones.

Warning: If you’e already installed TWRP or any custom recovery, please do not try to unlock it before installing the stock recovery again. It may brick your smartphone.

How to


  • Make sure your battery is more than 65%
  • Remove any lock screen security set up like finger print authorization or pass code.
  • Install ADB and fastboot in your PC ( Here is the simple guide to install ADB and fastboot)
  • All you need is a PC and a standard USB cable to connect your smart phone to your PC

Enabling USB Debugging

  • In your device, go to About phone and tap on Build number for few time. This will enable Developer options.
  • Go to settings–> developer option in your device and enable USB debugging. Below are the sample images where you can find both options.


USB DEBUGGING sample. Click to enlarge


  • Make sure you have installed Fastboot in your PC. Here is the simple guide to install fastboot
  • Now turn off your device.
  • Once the device is completely turned off, press and hold voume down+power button at the same time. (If you are using Samsung smartphone with bixby button , you should press and hold VOLUME up + BIXBY + POWER buttons)
  • This will boot your phone into fastboot mode.
  • Now connect your phone to your PC with the standard usb cable and wait till the phone is detected
  • Go to the folder where Fast boot is installed.
  • Open command prompt and move to the directory where you installed ADB or press SHIFT key and right-click on an empty space inside the folder and Select ‘Open PowerShell window here’ from the right click menu that appears. If your PC running on windows 10 the option will “Open command window here”

  • A PowerShell window shall open on your PC.
  • Now type the below command in the prompt.
fastboot devices
  • This will show you the list of devices connected to the PC.
  • Now type the below command in your command prompt. This will show the status of your bootloader of your device
fastboot oem device-info

  • Now re-Lock bootloader of your smartphone using below command.
fastboot oem lock

  • You can use below command again to confirm whether you have re-locked your bootloader successfully.
fastboot oem device-info


If you see false for “device unlocked” row in the prompt , then congratulations you’ve successfully re-locked your bootloader your bootloader :)

If you are struck , or if you need any help, kindly please us a comment.

Leave a Reply