Fairphone 4 is not booting in the last step

/e/OS Devices Fairphone
, ,
21

But I have the welcome to /e/OS screen on phone.
Still I didn’t lock the bootloader…

The terminal showed:
INFO: Done. The device will reboot now.
Rebooting OKAY [ 0.000s]
Finished. Total time: 0.000s

INFO: You can unplug the USB cable now. So I unplugged the cable.

22

This is obviously an issue with the community build. My FP4 is on 2.7-U official and the bootloader is locked.

23

I used the wrong zip file. (community)
Is it possible to reinstall /e/OS and continue with the ‘official’ zip file.
I want to reinstall via /e/OS via /e/OS Installer

I followed the steps but when I want to connect the device.
I’ve get this message
. . . . . . . .
Error on step: device-detection
Cannot execute command connect adb
The device is not connected Failed to connect: Cannot connect ADB Failed to execute ‘claimInterface’ on ‘USBDevice’: Unable to claim interface.
Proposal: Check connection and that no other program is using the phone and retry.
. . . . . .

24

Try

adb kill-server

and start again.

1 Like
25

Found it and it’s installing now.

26

You are using MacOS ?

Start a Terminal and type

find $HOME -iname adb

and you get something like

<path>/adb

from your previous install or plattform-tools-lastest-darwin.
Then type

<path>/adb kill-server

27

Hmmm… error…

Error on step: device-detection

Cannot execute command connect adb
Cannot execute command download
Cannot download
downloadAll error downloadAndUnzipFolder Error
current_file https://images.ecloud.global/official/FP4/IMG-e-latest-t-official-FP4.zip
Cannot close a ERRORED writable stream
Proposal: Retry by refreshing this page.

I refreshed the page but didn’t work.

28

Why don’t you use the command line installer from the official builds ?

You succeed using this method with the community build.

Edit: If you want to stay on A13 (T), you have to wait for the official build.

29

Why not using this build?
https://images.ecloud.global/official/FP4/

Android T(13)
IMG-e-2.5-t-20241108446629-official-FP4.zip [MD5 | SHA256]

30

Be aware of the rollback protection. 2.5 based on the android patch of Nov. 2024.

31

But I have Android 13 on my phone now.

32

Before you lock the bootloader please read the section

Caution: The FP4 comes with an anti-rollback feature. Google Android anti-roll back feature is supposedly a way to ensure you are running the latest software version, including the latest security patches.

Otherwise you may brick your phone.

33

So a quick update…
I managed to do the installation via easy installer on the website.
I went to Settings » About Phone » Android Version »
Here I found
Android Security update Oct 5, 2024
Vendor Security Patch Level saying Mar 5, 2024
Where can I find the version of ‘/e/OS security patch’ installed on my phone via the easy installer?

34

Downloads for FP4

  • /e/OS build : U community (Security patch: 2024-12-01)
  • /e/OS build : T official (Security patch: 2024-12-01)

To understand the difference between /e/OS builds check this guide

See Install /e/OS on a Fairphone FP4 - “FP4”

35

Btw I don’t get the message anymore about the bootloader unlocked (when I start the phone the message tells not to have any sensitive data because the bootloader is unlocked).

The current e/OS: 2.5-t-20241108446629-official-FP4
In ‘Updater’
There is a available update e/OS 2.7. Should I apply this update?

36

Thats up to you, but you should read this first:

There are some issues after applying the OTA-Upgrade.

I installed 2.7-U on my FP4 from scratch and have no problems by now.

37

For now thanks a lot!

38

I still got the message about the bootloader unlocked. So now this anti-rollback feature.
as I wrote:
Settings » About Phone » Android Version »
Android Security update Oct 5, 2024
Vendor Security Patch Level saying Mar 5, 2024
. . . . . . . . . .
In ‘Updater’ in find
The current e/OS: 2.5-t-20241108446629-official-FP4
. . . . . . . . . .
If I’m correct the version of /e/OS based on a security patch is more recent than the one on my phone. So to lock the bootloader should not brick my device right?

39

The short answer is yes.

Long answer - see example taken from the installation guide:

  • Rollback protection errors trigger if you install an update whose version number is LESS than the rollback index’s value stored on device.

and

Example 2

  • Your FP4 with Google Android has a Security Patch Level saying June 5, 2022.
  • The /e/OS build available says: /e/OS build : R official (Security patch: 2022-06-05)
  • In this example, the /e/OS build has the same Security Patch level than the origin, so the anti-roll back protection will pass, and you will be able to install /e/OS with no issues.

In your case the security patch of the build is newer than the android security patch.

40

So here we go
. . . . .
fastboot flashing lock_critical
. . . .
is not working in my terminal.