Relock bootloader OnePlus Devices

Download the latest FW files from here

1. Install TWRP (OnePlus 5) and Magisk if you don't have them yet.
   
2. Magisk should allow you to slide "OEM unlocking" to "enabled" in developer settings (THIS IS IMPORTANT)
   
3. Reboot to fastboot (Refer to my older post if you do not know)
   
4. Flash stock recovery via fastboot. (Refer to my older post if you do not know)
   
5. Run locking via fastboot flashing lock command
   
6. Allow it to reboot and upon start up it will say device corrupted (THIS IS NORMAL)
   
7. Boot to recovery via the warning start screen.
   
8. Once in recovery, sideload latest FW.
   
9. Done & have profit.
   

Please comment if you face any issue or for any query.

Unlock & Relock bootloader using Flashtool (Android-Sony Xperia)

Unlock your bootloader

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a) download and install latest Flashtool from here

b) start Flashtool and click on BLU button on the top

c) turn off your phone and when Flashtool shows pop up window, connect phone to PC with holding volume down button (to boot in Flashmode)

d) click on get unlock key button, it will switch you to Sony Mobile website (For Sony Phones Only), here complete all boxes

e) copy IMEI form Flashtool to Sony Mobile site, than you will get unlock code to your mailbox

f) copy unlock key to Flashtool window and than click unlock

g) connect phone with holding menu button when Flashtool shows pop up window

h) wait to unlock finish.

Relock your bootloader

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a) start Flashtool and click on BLU button on the top

b) turn off your phone and when Flashtool shows pop up window, connect phone to PC with holding volume down button (to boot in Flashmode)

c) just click on relock button and your bootloader is locked for now


For Flashboot Mode: Press back Key or for Touch Navigation Key model, Press Volumn Down Key

For any queries, Please leave comments bellow.
HELP MAKES ALL HAPPY