Reverting to Stock Rom: The phone is encrypted

/e/OS Devices Samsung
1

Hello :wave:!

After upgrading to an /e/ Fairphone, I decided to recycle my ol’ Samsung S9+ by giving it to my father. But, not wanting to give him a modified android with which he might get troubles running some apps, I decided to roll it back to its stock rom following /e/'s guide.

The trouble is that after flashing everything, I get this worrying message (loosely translated from French):

Your phone is encrypted for security measures. To boot your phone, enter your password.

I entered some passwords I frequently used, to no avail. I have tried multiple ROMs, same thing (including one I was nearly sure didn’t require any password to boot, as I used it to solve a past issue with /e/.). My only remaining theory is that when /e/ encrypted parts of the phone for security, reverting to stock rom didn’t get fully rid of that encryption, and now the key is lost.

Does anyone here have any idea? I guess I could give him an /e/phone, but, would even reinstalling /e/ recover anything at this point ?

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Something just like this is seen in TWRP using Android 10. When TWRP asks you the password and you know none exists you should press cancel to pass the default_password and you should be in business.

However I am surprised you see this if you are using Windows and Odin from Download mode. So if you are seeing this in the Samsung Android recovery perhaps you could try to press cancel. Edit, if you did this I would expect you next to be forced to delete data (again!) and boot to system should include no password.

I expect Android 10 requires encryption. I expect Odin to have deleted the data partition, so I would expect nothing residual from /e/.

(In case I am missing something, perhaps you could just clarify if you are asking about “pure Android Samsung”. Is there any possibility that Odin did not complete the full stock ROM process? But you say you repeated it. Edit, I realise this is newer than my experience, so perhaps in Android 10 it would be necessary / wise to delete data with TWRP before Odin?)

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Hello, thank you for your answer :slight_smile: !

When TWRP asks you the password and you know none exists you should press cancel to pass the default_password and you should be in business.

I cannot do that on Samsung’s UI, unfortunately.

Edit, if you did this I would expect you next to be forced to delete data (again!) and boot to system should include no password.

How would I do that without TWRP (I guess it’s gone since I installed Samsung’s ROM)? Maybe reflashing /e/ to get it back?

I expect Android 10 requires encryption. I expect Odin to have deleted the data partition, so I would expect nothing residual from /e/.

Okay! I’ll try with an Android 9 ROM to see.

Edit, I realise this is newer than my experience, so perhaps in Android 10 it would be necessary / wise to delete data with TWRP before Odin?

Indeed, if Android 9 does solve the issue, I’ll try to have this reported to /e/'s doc team to update their doc.

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I have been reflecting since my earlier post (just to clarify my first paragraph was only to set out my starting point regarding default_password, part of encryption, rather than part of TWRP, afaik).

In an Android/Samsung organised ROM replacement my assumption is that the data partition is wiped.

  • As encryption is involved in Android 10, we can say wipe data is required.
  • If change of Android version is involved, we can say wipe data is required.

As Odin is “semi official” I kind of made an assumption data would be wiped – this might well be wrong on my part – perhaps it would be “your job” to wipe data.

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One file Samsung firmware preserve “home” (/data partition),
You may have to use Four or Five files composed Samsung firmware in a way to replace the “home”

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That’s how I’m doing it (I’m following /e/'s tutorial).

For some reason, I’m unable to flash the Android 9 Samsung ROM. I think that’s due to the window’s virtual machine quirk, I’ll have to find a bare metal Windows machine to further test it on.

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I had expressed it rather badly but the guide puts it differently

Tip: On some devices if you are stuck at the boot screen, you can try to do a factory reset from within the recovery to get the phone to boot.

This would be expected to delete data, but was it impossible?

(Please note that my use of required in my last post was more about my expectations than technically accurate!)

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Tip: On some devices if you are stuck at the boot screen, you can try to do a factory reset from within the recovery to get the phone to boot.

Oops, didn’t read that :melting_face:…

How did I just not think of that solution to delete the data partition… But, it does indeed then validate the idea that somehome /e/OS w/ Android 10 → Samsung Stock ROM w/ Android 10 does not delete the data partition…

Anyway, thank you so much everyone for the help!

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