{% include alerts/danger.html content="The FP4 comes with an anti-rollback feature. Read the paragraph marked `Caution` in Requirements section of this guide, before proceeding." %}
Once you have completed the above steps and before rebooting you can and should lock your Bootloader.
Once you have completed the above steps and before rebooting you can lock your Bootloader.
1. Lock critical partitition with the following command
1. Lock critical partition with the following command
-`fastboot flashing lock_critical`
- Approve with <kbd>Voume +</kbd> then <kbd>power</kbd>
1. Reboot again your device into bootloader, and plug it to your computer
-Approve with <kbd>Volume +</kbd> then <kbd>power</kbd>
1. Reboot your device into bootloader, and plug it to your computer
1. Lock the device with the following command
-`fastboot flashing lock`
- Approve with <kbd>Voume +</kbd> then <kbd>power</kbd>
- Approve with <kbd>Volume +</kbd> then <kbd>power</kbd>
{% include alerts/success.html content= "Congratulations !! Your phone should now be booting into /e/OS !! "%}