Happy to announce that I succeeded in downgrading my phone from android 12 to 11, and installing /e/. I will do my best to explain how I managed to do it, as I haven’t much knowledges in this specific field.
How to enter boot modes on s10e
Check for an other device here
Recovery mode :
With the device powered off - Reboot and immediately hold Volume Up + Bixby + Power while the device is connected to a PC via USB cable Download mode :
With the device powered off - hold Volume Down + Bixby and connect USB cable to PC
Downgrading from android 12 to 11
This can be easy or it can be hard because of anti-rollback protection (samsung unallowing you to downgrade).
Check you CSC on your phone by dialing *#1234#. You can also have this number in recovery mode. Mine was G970FOXMEGVA4.
You need to find a stock rom which has a bit (the bold letter in my CSC) which is equal or higher to be allowed to downgrade.
I downloaded on sammobile (you need to create an account) the version G970FOXMEFUJ2 . In both, same binary “E”, no anti-rollback protection, you can still downgrade. Once your BIT passes to F (after an update), you’ll be in trouble and I don’t know how you can do it…
Once you found your stock rom, you just need to flash it through odin as it is described here for example.
Flashing TWRP
This was a difficult part but I would make it easy for you if you have the same samsung model as I do.
The regular way to flash TWRP doesn’t work with samsung s10 series.
While flashing TWRP you need to flash at the same time a vbmeta image with verity disabled.
A stock device is protected by Android Verified Boot. This is implemented as a vbmeta partition that contains cryptographic digests for verifying the integrity of boot.img, recovery.img and other partitions/images. Flashing TWRP without first flashing a vbmeta image with verity disabled will render your device unable to boot.
Quoted from TWRP website
You will have to follow this simple procedure :
Prerequisites: Samsung USB drivers, Odin v3.14.1
If you already have the bootloader unlocked you can skip to step 6.
- Make sure OEM Unlock is ON in developer settings;
- Turn off the phone;
- Use vol down + bixby key + usb cable plugged to a pc to start the phone in download mode;
- Long press vol up then confirm you want to unlock bootloader (this is needed one time only);
5.** Please be aware all your data will be erased including internal storage and phone will reboot!!**- Let the phone boot normally, pass the setup and connect to internet (wireless or mobile data) in order to unlock RMM;
- Make sure OEM Unlock is ON in developer settings;
- Turn off the phone;
- Use vol down + bixby key + usb cable plugged to a pc to start the phone in download mode, short press vol up to confirm you want to go to download mode;
10.** If by any chance you see RMM state=Prenormal or KG state=Prenormal, redo from step 5!**- Download appropriate TWRP .tar file according to your device
- Download avb disabled vbmeta .tar
- Open Odin v3.14.1 and place the downloaded TWRP .tar file in AP tab, downloaded vbmeta .tar file in CP tab and click Start - once you press start grab the phone and press vol up + bixby + power to force it boot straight in TWRP after flashing
!! Only if coming from full stock firmware
- In TWRP home screen press wipe - format data - yes
- Download and flash multidisabler-samsung-3.* zip to disable security and encryption.
I succeeded using twrp-3.6.0_9-1-beyond0lte.img.tar which is the latest version working with android 11. The versions above are for android 12. This version is for samsung galaxy s10e europe only.
I tried several older versions but it didn’t work.
In download mode, you need to see these lines if you want to be able to flash TWRP
KG state=checking
FRP lock = off
OEM lock = off (u)
Secure download = enabled
If not, you’ll probably have this error message “an error has occured while updating the device software. Use the emergency recovery function in the smart switch pc software” and you’ll have to flash the stock rom again.
Even while doing steps 5 to 8 as described above, I still had KG state=Prenormal.
I managed to pass it to “KG=checking” following instructions in this video until 3:50.
I haven’t done the step below (I forgot). I don’t know if it was a mistake or not as I don’t know what it was for.
- Download and flash multidisabler-samsung-3.* zip to disable security and encryption."
Installing /e/
Now you just need to follow the rest of the instructions.
If any native english want to correct my mistakes I won’t be mad. I hope it’s not too bad.
Good luck and have fun