TWRP on /e/OS S does not ask for decryption


I had /e/OS R (Android 11) with TWRP on my Fairphone 3. I had to reinstall /e/OS which now is S (Android 12).
At the end of the installation process of TWRP there was the error Failed to mount '/product' (invalid argument). I can boot into TWRP but it does not ask for decryption pattern/PIN.
I formatted data because that helped a long time ago with the same issue. This time it does not help.
Is current TWRP 3.7.0_9-0 not compatible with current /e/OS for Fairphone 3?
Does anybody have it working with /e/OS S? If so, any idea what might be the issue here?

Fairphone 3/3+ TWRP currently can’t decrypt /e/OS Android 12 encryption.

It’s working, but it can’t decrypt user data, which is not a guaranteed TWRP functionality …

Same with stock OS by the way, introduced with an OS update within Android 11 …

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Thank you for your answer.
That sounds horrible. No way to backup and manage the data partition in TWRP what saved me several times before.
The website says that 3.7.0_12-1 (only) in the Android 12 branch (for devices that come originally with Android 12) supports encryption, not for devices in other branches. The Fairphone 3 came with Android 9 and thus is in the Android 9 branch 3.7.0_9-0. I am afraid that this means that TWRP will never support encryption on that device with Android 12+
To stick with Android 11 is a security risk because the /e/ team does not maintain it any more.

Thank you for the link.
The tools are for backing up apps (data), not the whole data partition what I needed a few times to recover the phone.
On my rooted device I have an app for automatic app and data backup. That helps in most cases. The other cases must never happen again, but probably will. Restoring apps and data after a factory reset takes a long time and does not restore all the system settings.

Do you know anything about the Failed to mount '/product' (invalid argument) error? I found many similar posts on the internet but none was related to this special issue.

The tools also have a full backup script, but I didn’t try these tools yet myself, so I can only go by what I’m reading in the documentation there.
Else … the tools require root or at least Rooted Debugging (which is root only for ADB), and with this you should be able to access all of the data partition via ADB yourself.

Unfortunately not, sorry.
I never installed TWRP on my Fairphone 3, I just boot it with fastboot when I need it.

Thank you for pointing that out, I have overlooked this.

Nevertheless I miss the quick procedure to just tick the shortcut of a Tasker task that reboots to recovery where an OpenRecoveryScript runs the required partition backups and then shuts down the phone. But wailing doesn’t change anything.

Edit: These scripts need a Linux system with several requirements.

These scripts and other workarounds only work from the booted system because that is the only state when the data partition is decrypted. If this is not possible data cannot be restored in TWRP. And that is what I need the full backups for. :frowning_face:


If you backed up using the scripts, you would of course restore using the scripts.

TWRP is out of any consideration in this regard as long as it can’t work with the encrypted data partition.

By the way, the maintainer for TWRP on the Fairphone 3/3+ is currently trying to get it working better again, you can follow proceedings here …
Several issues are being worked on, apparently it’s complicated, there’s no officially distributed update solving everything for different OS flavours yet, but at least there’s hope.