Trapped in fastboot mode with locked bootloader and corrupted custom ROM

the fairphone was repaired


Have the same problem. Flashed e/os and locked the bootloader. No error appears. I used it one day but some bugs are killing the experience. The fingerprint sensor are buggy, the camera have only 12mp and the usb preferences don’t work and the usb c to 3,5 audio jack. So yesterday I decided to flash the stock ROM. Downloaded the lasted from the manual and flashed it. After booting the os run without issues. The last step is lock the bootloader. So I looked it in the fastboot. Reboot and run into the same situation. Thank for all the information guys. At least i wrote the support. The is nothing more to do…

I don’t know why something like that happen by using the official files? Maybe a wrong date in the phone? I only an android app developer and use adb the most time. But the hand full of people have the same bug. It seems to be a bigger problem that I think. I hope the Fairphone Devs find the issue.


this is more than annoying and happens not only on /e/OS, also on iodé.
There are the only two official custom ROMs at the moment.
calyx is developping their OS for the FP4, but they don’t release ist. There is one difference, calyxOS for FP4 will base on A12L not A11.
But I’m sure, if they bring it in the field and do not only test it under laboratory conditions, the users will run into the same problems. Because one of the main focus and philosopie at calyx is to lock the bootloader again.

in my opinion, what you hear lately, this is a homemade problem of firphone with the FP4
hopefully they realize it and address the matter also…
On the other hand, this will be a real nuisance for the community and for FP itself. Is not good advertising…


Yes i bought the phone with the idea of flashing other firmware special ungoogled os. So if the problem is not solved in the future the idea of the phone dies in the software part. And i won’t send every time the phone to a repair station to get the stock image flashed. I have the equipment to replace the parts and flash it myself. That’s the spirit here.


Maybe I don’t understand the topic because I haven’t read every comment here. But if you have access to fastboot, you are able to flash a (new) recovery, right? And with a recovery you can do a factory reset and flash a new ROM. How come the phone got bricked? And is this really a Fairphone issue? From the bits that I’ve read the problem is with the /e/ OS ROM, not with the Fairphone OS, which is the ROM Fairphone has control over. Is that about a correct summary and conclusion? If so, then I’ll remove this issue from this list.

You can’t flash anything if the bootloader gets locked and you can’t unlock it again if get_unlock_ability is reset to 0 (like in this case) and the system isn’t able to boot.

This isn’t a /e/ issue, similar problems have been reported for every OS, including stock FPOS. I myself am running one phone with CalyxOS right now that got get_unlock_ability reset to 0, thankfully I didn’t lock the bootloader and didn’t brick.

I’m not exactly sure who should “own” this issue, but there are Fairphones that are getting bricked and so far no one seems to have a definitive answer on what’s causing it.


and unfortunatly no statement from Fairphone so far…

They have a warning that they do not recommend locking the bootloader before the section that describes how to lock the bootloader. Imo they should add a warning on the FPOS download page, because that is where people have to go to get the required files, and if you know how to (un)lock a bootloader those instruction pages are kinda optional.

They acknowledge the problem, which is at least something


Hmmm okay. I haven’t tinkered with my Fairphone in that way yet, and probably won’t because the default ROM is fine for me. On my Pixel I can lock and unlock the bootloader from fastboot. If you lock your bootloader, but your ROM doesn’t have a properly signed ROM, then it indeed won’t work. This is the case with many, if not all, custom ROMs. The only custom ROM I know that properly signs their ROM is Graphene OS.

If this bricking doesn’t happen with the original Fairphone ROMs, but only with 3rd party ROMs, then I would say it’s not a Fairphone issue. So the question then becomes, is this issue happening only with 3rd party ROMs? Because then it’s up to the custom ROM developers to include proper secure boot support, isn’t it?

If I’m wrong then please give some examples or more details. I’m just figuring out if this one needs to be listed in that wiki topic about issues relating to the FP4. Because if it’s a 3rd party issue, it might never be fixed and then it’s just a stain in that list that will never be removed.

Several phones bricked when manually flashing FPOS, so there def is an issue not only related to Custom ROM. So I think its something every developer (FP and Custom ROM) needs to be aware off

Somehow Murena might have recognized issues


Can you lock the bootloader with other Fairphone models and custom ROMs such as /e/ and Lineage? Just checking if these ROMs provide support for other phones. Were the people that flashed FPOS experienced with flashing? Last time I saw the documentation to re-flash FPOS I wasn’t really impressed about the simplicity. For a Pixel you just run the script and then just sit back and wait. If people don’t follow the manual steps correctly for flashing FPOS, then locking the bootloader might indeed have a disappointing result.

Sorry for playing the devil’s advocate here. Not trying to be difficult. Just want to make sure this issue is something that Fairphone can fix or is an issue for the 3rd party ROMs.

I think hundreds of people use Custom ROM on the FP3 which is an A/B device with locked bootloader as well, and most people re-lock there bootloader. This has all been discussed over and over and over again the last days maybe you want to read the other threads first and search the forum for FP3 related topics

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I just want to verify if this issue is really something in the domain FP can solve :wink: If this is really not just a 3rd party issue, then I’ll just leave it there in that list. I remain a bit skeptical, but since someone mentioned FP hasn’t replied to this issue, I guess something must be up.

I understand what you said and still reading other topics will help you to exactly answer this question

Not sure what is difficult about extracting a ZIP folder and double click “flash_fp4_factory.bat” followed by a yes confirmation? Seems to be the exact same process as on the FP2 and that was really simple

That’s for sure not hard indeed, also not for Linux, it seems just to run Maybe this is a recent change? I came across a documentation page with a lot of manual steps. I’m a senior Linux systems architect and even I was like; whut? Good to see it has improved.

You can lock the bootloader on /e/, iode and CalyxOS (and stock FPOS of course) and all of them actually encourage you to do so, so yeah this is a real problem.
If something goes wrong when locking the bootloader and get_unlock_ability was somehow (no one has figured out how) reset to 0, the phone is bricked and can only be repaired by Fairphone.

Since this is a flag that should survive factory resets (and it survived the phone being flashed back to stock on my devices), I’d expect Fairphone to have knowledge about where it’s stored and what could be messing with it.

Even if this turns out not to be a Fairphone problem, some help for the community how to figure it out would be really appreciated. I’m pretty sure they don’t want unnecessary work for their support staff either…


I got my FP4 today and I’m facing the same problem. I cannot unlock anymore and the phone won’t boot either. Does anyone figured anything out yet?

Nope, if your phone is not booting, the bootloader is locked and you cannot unlock you are unfortunately out of luck.
If you boot into fastboot mode and connect your phone to your PC, what does fastboot flashing get_unlock_ability return? If it returns 0 you will have to send it to get it reflashed.

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Huh that’s a bummer, it returns 0 indeed. That’s kinda unlucky I was so hyped. Thanks for the quick reply though.