Hi, I just tried to install the September OTA update based on the Magisk OTA installation tips however the installation of the update fails during step 1. At least I am still rooted on the August patch level. How can I update my phone without losing data? I thought about reflashing system and trying the steps again but I don't know where to get the factory images for 9.6.6.0 (August) or 9.6.8.0 (September). This is my first A/B phone by the way. Thanks in advance.
OTA failed on rooted device
- Thread starter rfkd
- Start date
On this page only the ROM for 9.6.4.0 (July) can be downloaded. Later versions are not available anywhere? If not I have to flash July with fastboot, root again and retry the OTA update?
No, the only fastboot image at the moment is this. It should be not a problem downgrading, as long as the same Android version is involved (Oreo 8.1 in this case).
And yes, you can flash that fastboot image and then follow my guide to install Magisk, and then install the OTA update always following my guide, just to test that everything is working as intended.
This did not work. Seems like using flash_all_except_storage.bat was not the right choice, my unlock pattern during booting is not accepted. 
So you must use flash_all.bat, but you will lose your data. At the moment the data is in the phone memory, but is encrypted and you probably lost the decryption key when you flashed the other partitions, so not a great lose anyway.This did not work. Seems like using flash_all_except_storage.bat was not the right choice, my unlock pattern during booting is not accepted.
I don't know if there is a way to get your data back.
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