Locking the Bootloader will factory reset your device according to installation instructions for FP4?

[piero]

@BDesco

the below commands will factory reset your device

that lead to a clean /e/OS starting as new, without any user activity on the device.

@piero

If you plan to relock the bootloader after the installlation

this is not mandatoty, and only available with Official version, why relocking ?

Most important thing to take care about is the “android Security Update" aka "Security Patch Level” date (SPL) included in the installed Operating System on your device at time of the unlock.

new version on witch you want to relock the bootloader, must included a NEWER (or the same) “android Security Update" aka "Security Patch Level” date (SPL),

otherwise you risk to change your device into Brick.

@piero

3. Finaly, relock the bootloader (optional)

only how it is mentionned at the bottom of the official instructions in the “Smartphone Selector” for your device → “Official or Community install doc” for your device → “Command line” install page for your device !

only if the android security update in the previously installed OS was

older than the android security update included in the version you want to install

only if the newly installed version is an Official one, not a Community version.

re-enable Developer Options, USB debugging and allow OEM unlocking

with the device in bootloader mode,

• Open a terminal from the “/platform-tools” location
• and check bootloader status by running :

./fastboot oem device-info

./fastboot flashing get_unlock_ability

if the return is 1
→ you will be able to relock

if the return is 0
→ you will not be able to relock now, it is advised to reboot or

reinstall FairphoneOS and re-enable Developer Options, USB debugging and allow OEM unlocking . (to get =1),

and then reinstall /e/OS.

[HOWTO] a Safe Guide to install /e/OS