Thank you for your effort, and hints/help.
I had only written the initial post in the hope of a miracle, that there would be another way out than asking fairphone support for an EDL to clean the bootloader.;--())

@MrT10001 said in fp4: another brick in the wall:

... If Law enforcement can do it and do it on locked, encrypted iPhones (they are difficult to get into iOS unless you have expensive tools), expect the criminal fraternity to have to ability to do it.

I don't have $2k to buy an EDL device, and I certainly don't belong to a criminal organisation, ...damn, now I could use something like that
...;-)lol

No I don't have a FP (yet) as they are expensive here in comparison to other devices and from what I have seen

agree! But it was one of the most comparable thing I found for linux- and lineage-derivates without PWM.

and read have issues that involve sending them back to FP to recover - read here.

I should have read this things before!;-)

@MrT10001 said in fp4: another brick in the wall:

Can you boot into recovery?

Nope imo.
Not by ButtonUp+Power, not by decision in bootloader and not by fastboot:

# ./fastboot boot recovery
fastboot: error: cannot load 'recovery': No such file or directory
# ./fastboot reboot recovery
Rebooting into recovery                            OKAY [  0.003s]
Finished. Total time: 0.053

always running into this:

If you get into recovery, can you adb sideload the stock Android (zip file) ROM?

...I really don`t know how "recovery" mode is looking at fp4. Send a photo, pls.

You mean this: FP4-FP4K-factory.zip? Nope!

Some reading:

here

here

may give you some ideas.

Nope, it's about something else entirely, I take it?
(or I don't understand what you're trying to say, sorry?)

But I found this:
https://forum.fairphone.com/t/fairphone-stuck-in-fastboot-mode-bootloader-unlocked/85968/7
From AlphaElwedritsch, Jun 2022:

fastboot flash recovery_a iode-3.0-20220530-FP4-recovery.img
fastboot flash recovery_b iode-3.0-20220530-FP4-recovery.img

Where to get that both recovery.img for Ubuntu Touch?
I would like to give it a try. This fastboot-mode and the EDL-Mode are the only screens I could reach. No "adb", no "recovery" imho.

An unlocked bootloader is a must to install any no stock Android or other operating system on a device. There are some risks but are minimal if you are careful.

I didn't talk about a unlocked bootloader which is a "must to install any" OS.
I talked about a stolen or lost phone, which is really too easy to crack, steal data and sell with new clean OS with a unlocked bootloader. That locking is a security measure like a "Boot Sector Protection" with password in PC-Bios. But that's completely different topic.;-)))

Hi there,

I am a little bit lost. I installed actual Ubuntu Touch (Focal Fossa) on my Fairphone 4 but I made a fault at bootloader and need a hint, what to do now.

The story:

• got new FP4 with Android 13

• target: get rid of google and android, get a repairable linux phone

• followed this instructions: https://devices.ubuntu-touch.io/device/fp4/

• 1st installed Android 11 as requested with fastboot as mentioned here: https://support.fairphone.com/hc/en-us/articles/18896094650513-Installing-Fairphone-OS-Manually
  →here I get the most confusion because I wonder why I only could see my device on „fastboot devices“, but not on „adb devices“
  -but followed this instructions to unlock the bootloader:
  https://support.fairphone.com/hc/en-us/articles/10492476238865-Manage-the-Bootloader
  -getting unlock code
  -OEM-locking unlocked
  -# ./fastboot flashing unlock
  -# ./fastboot flashing unlock_critical
  -then installed Android 11 without faults:
  File name: FP4-FP4K-factory.zip
  Version: FP4.FP4K.A.179.20230116

-installed „ubports-installer_0.10.0_linux_amd64.deb“, running fine without any probs
-tested UT: phone calls, wlan, tethering, etc., seems working nice and smoothly, so decided to keep this OS in my fp4
-but as I often have to reboot, I saw the bootloader-warning as in https://forums.ubports.com/topic/6689/stuck-at-bootloader
I followed my understanding of security and had read it somewhere(?) during my research and:
-# ./fastboot flashing lock_critical
-# ./fastboot flashing lock
damned stupid fault!!!;-(

Now I hang here like some other people before:
https://forum.fairphone.com/t/trapped-in-fastboot-mode-with-locked-bootloader-and-corrupted-custom-rom/80985/287
There last solutions (as I understand with my bad english) would be to send phone to support to unbrick. Getting repaired it by EDL on your own seems possible for fp3, but there is no „firehose file“ for fp4.

So, what do ya think of the misery?

In the meantime, is there any way, apart from Fairphone support, to fix the problem?

As far as I understand it, an "unlocked" bootloader always carries the risk that (a) apps/programs could infect the kernel directly and (b) if the phone is stolen, the thief can easily sell the device with a clean, newly installed operating system. Is there a way to lock the bootloader from within UT (OEM lock)?

Btw: I think it`s easy to get into the EDL-mode:
within bootloader:
$ lsusb
Bus 004 Device 016: ID 18d1:d00d Google Inc. Xiaomi Mi/Redmi 2 (fastboot)

device off
loud up & loud down at the same time
connect usb to PC
->dark screen, but:
$ lsusb
Bus 004 Device 018: ID 05c6:9008 Qualcomm, Inc. Gobi Wireless Modem (QDL mode)