I managed to do, a partial, dirty upgrade, so no need to reinstall all apps and data.
But, to keep it save, make a copy of all you data and pictures, contacts, messages, to you Pc or to the cloud, it’s always good to make a good backup.
You need a good/latest ADB and fastboot install.
Need good Sony Xperia USB drivers, download here and install, How to install Sony Xperia Drivers Manually (Super Easy Guide) , and you will have them.
Download the files.
e-2.6.3-u-20241219455571-community-xz2c.zip
recovery-e-2.6.3-u-20241219455571-community-xz2c.img
For ease of use copy these files,
e-2.6.3-u-20241219455571-community-xz2c.zip
recovery-e-2.6.3-u-20241219455571-community-xz2c.img
, to same directory where ADB.exe is installed.
In my case that is C:\Program Files (x86)\Android\android-sdk\platform-tools
On device, enable USB debugging.
Connect USB
On computer
Windows Start
Type CMD → rightklick start as Administrator
In CMD
cd C:\Program Files (x86)\Android\android-sdk\platform-tools
adb devices
On device there will pop up a screen, asking for permission, accept.
adb reboot recovery
Device wil reboot into recovery
On recovery screen
Advanced
Reboot to bootloader.
Screen wil be black, no fastboot/bootload screen, only the notification led will light bleu.
to check if you are in fastboot/download mode
On Pc
fastboot devices.
if error then probably not the right USB drivers
if no error
fastboot flash boot recovery-e-2.6.3-u-20241219455571-community-xz2c.img
Now begins the button hassle again for booting again into recovery.
Need to power of with Power button.
And as device powers down it probably will reboot directly.
Now quick press Power and Volume down buttons together, hold and wait.
If you fail to boot into recovery, power down again and try again power on with Power + Volume down buttons.
If you boot into recovery, check if it say’s 2.6.3.
Of not, you have to flash again.
If recovery say’s 2.6.3
In Recovery screen.
Apply update
Apply from ADB
On Pc
adb -d sideload e-2.6.3-u-20241219455571-community-xz2c.zip
Then just wait, the screen is almost white , when ready you will see a message on the screen.
On Recovery
Reboot to system.
And all should be working now.
But, to be save, make a copy of all your files, before you start.
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