I have a Fairphone (Gen. 6+) and I’d like to re-lock the bootloader, following Fairphone’s official guide, but I’m unsure whether it is safe in my situation.
What I did
Bought it with Fairphone OS (Android 16, build FP6.QREL.16.82.0), unlocked the bootloader (flashing unlock, then flashing unlock_critical), and installed /e/OS (Android 16 build) with the manual method.
A few days later I returned to stock Fairphone OS, using the official package FP6.QREL.16.111.0.20260831102426_WS1Q-factory and its flash_fp6_factory.command script on macOS. All files verified OK with SHA256SUMS, and the script ended with “OPERATION SUCCESSFUL”. It mentioned “Deleting factory reset partition” and “Successfully reset rollback index”.
The phone boots normally and is fully set up. I have not put any personal data on it yet.
The problem
In Developer options, OEM unlocking is greyed out and off, with a note saying the bootloader is already unlocked.
In fastboot, fastboot flashing get_unlock_ability returns 0.
My questions
Is get_unlock_ability: 0 expected after flashing the official factory package on an already-unlocked FP6/FP6+?
Is it safe to run fastboot flashing lock_critical then fastboot flashing lock in this state? I’m afraid that if the phone fails to boot afterwards, I won’t be able to unlock it again.
Is there a supported way to get get_unlock_ability back to 1 without risking a brick?
Is it OK to leave the bootloader unlocked long term, or does Fairphone strongly recommend relocking on stock OS? I’m concerned about security, and about Google Wallet working with an unlocked bootloader.
I haven’t run any lock command. Thank you for your help!
Thank you for the pointer. I searched the forum before posting and read the “Guide to bootloader and bricking [2025]” and Fairphone’s “How to unlock or lock your Fairphone’s bootloader” page. I could not find a topic matching my exact situation, so here are the details.
Device: Fairphone (Gen. 6+), shipped with Fairphone OS Android 16 (build FP6.QREL.16.82.0, security patch 5 June 2026 - [please double-check this build number on your phone]).
History
Unlocked the bootloader (fastboot flashing unlock, then unlock_critical) and installed /e/OS (official build 4.3-a16) with the manual script. I did not use the web installer.
Returned to stock Fairphone OS with the official package FP6.QREL.16.111.0.20260831102426_WS1Q-factory (Android 16, security patch 5 Sept 2026). All files verified OK with SHA256SUMS and the script ended with “OPERATION SUCCESSFUL”. Its output includes “Deleting factory reset partition” and “Successfully reset rollback index”.
The phone boots and works normally. It is set up, with no personal data on it.
Current state
fastboot flashing get_unlock_ability returns 0.
In Developer options, OEM unlocking is greyed out and switched off, and the phone says the bootloader is already unlocked.
The bootloader is still unlocked. I have not run any flashing lock command.
Why I’m asking
The guide says that if get_unlock_ability returns 0 one should enable OEM unlocking again in Developer options. That is not possible here because the toggle is greyed out. Several FP6 threads report phones that could not boot after relocking with OEM unlocking disabled, so I don’t want to try.
My goal is to relock the bootloader, since I want a locked, secure phone and I’d like Google Wallet tap-to-pay to work (an unlocked bootloader fails Play Integrity).
Questions
Is get_unlock_ability: 0 expected after flashing the official factory package on an already-unlocked FP6/FP6+ (probably because of the frp partition rewrite)?
Is there a safe way to get it back to 1 without a brick? Would reflashing help, or can only Fairphone support fix it?
Has anyone relocked a FP6+ on the current stock Android 16 build, with or without this problem?
Is leaving the bootloader unlocked long term considered acceptable on stock Fairphone OS?
Thank you for your help. I will report back with whatever I find.
The info is spread, there is not 1 topic. The SPL is important and you dont mention the e/OS version you are coming from. I would not lock when get unlock ability is 0 as the risk is higher to brick.
In addition to what @yvmuell has mentioned:
I think the same has always happened on FP4/5/6, too, when reinstalling FPOS after e.g. /e/OS: that get_unlock_ability reverts to 0 and the slider is greyed-out.
But in the mentioned topics you might also find the information that unlock_ability was still “1” just after the OS installation and before booting into userland (see e.g. here or here).
As you haven’t yet put any personal data on the phone you might still try that out (an OS reinstallation without booting the phone).
Thank you, you are right, here are the missing details.
Software history and security patch level (SPL)
Original Fairphone OS: Android 16, SPL 5 June 2026 (build FP6.QREL.16.82.0 - [please double-check]).
/e/OS: official build 4.3-a16 (IMG-e-4.3-a16-20260917677552-official-FP6), SPL [to fill in from the /e/OS download page].
Now: Fairphone OS FP6.QREL.16.111.0.20260831102426_WS1Q-factory, SPL 5 September 2026.
Other facts that may matter
The bootloader has been unlocked the whole time, and I never ran any lock command at any point.
Before installing /e/OS, fastboot oem device-info showed every “Rollback index” at 0.
The Fairphone flash script reported “Successfully reset rollback index”.
Currently get_unlock_ability returns 0 and OEM unlocking is greyed out (the phone says the bootloader is already unlocked).
I agree with you: I will not lock while get_unlock_ability is 0.
My remaining question: is there a safe way to get it back to 1 on an already-unlocked FP6+ when the OEM unlocking toggle is greyed out? Or is Fairphone support the only route? Any pointer to the right topic is welcome, as I could not find one that matches exactly.
I also recently bought an FP6+ with Android. With a lot of effort, I managed to install the latest /e/OS version on it. I didn’t lock the bootloader because that would only be safe to do after an update, as the Android security update was set for September 1st. After that, I reinstalled the latest version of Android quite easily. That SPL is dated September 5th, which was also the date before I installed /e/OS. I locked the bootloader again, and that went well. So, apparently, the SPL doesn’t have to be a later date; it can also be the same date.