[Xperia Z3 Compact General] HvdW:
Introduction

XDA members devil188, nailyk and Dobsgw created an Omni ROM for Xperia Z3 Compact. https://goo.gl/omqsSP

A great job.

It works, still has some bugs (20171213) but it is good enough to use as replacement for MM as it is now.

Many are afraid to root their device.

- Warranty void

- Device going black

- Not familiar with the steps to take.

Now is the moment to upgrade your device to Oreo

- Warranty is void anyway because your device is more than 2 years old. (test by clicking on the Support app on your device)

- Device going black ( that is your own risk and I take no responsibility whatever if you brick your device)

- This guide takes you by the hand (step by step)

- The rewards are manifold.

Your devices will be as new.

- Oreo has the latest security updates

- You can allways revert to stock MM

The biggest risk in my opinion is unlocking the device and losing DRM keys which affects low-light photo quality.

This risk can be overcome by making a backup of the TA partition and in case that does not work it can partly be repaired.

Let's start.

STEP 1 Backup

You don't want to lose important stuff, so you want to make a backup first.

Method 1

Use Xperia Companion and make a backup to your PC

Method 2

Use the Xperia Transfer Mobile app

Make a backup to the cloud or to SD card.

Method 3

Use Google.

A good explanation can be found here.

Method 4

Use adb

With adb you cannot restore on a non rooted device but we will go rooting the device anyway.

To read about adb look here.

When begin your backup take some extra safety precautions.

- Whatsapp -> settings -> chats -> backup, for a fresh backup

- Whatsapp extra security copy the Whatsapp directory from device memory to SD card or to PC

- Signal -> Import and Export and copy SignalPlaintectBackup.xml to SD card renaming it to SignalPlaintextBakup-201712XX.xml

- Copy DCIM (your pictures) from internal memory to SD card or to PC

- Google backup settings -> accounts & sync -> sync everything

- Copying can be done with TotalCommander

I suggest to try the different methods of backing up and don't forget to test restoring.

STEP 3 Install and use ADB

Because you will root your device and need to make a backup of the ta partition it is important that you are able to use adb.

I made a post on that subject here.

Most of you probably are on Windows 10.

In this ADB and Fastboot for dummies is explained how to install the drivers for Windows 10 (and 8)

When you read it carefully it will be no problem to set it up.

Warning!

Flashtool, which is mentioned in the setup for installing the drivers on Windows, can be polluted on some download sites with virus and/or malware.

Take care!

Drivers from Sony can be downloaded from here.

STEP 4 Root your Locked device

You can root your locked device by following the steps from this thread carefully.

I did'nt manage so I unlocked my device.

STEP 5 Backup DRM keys & TA partition.

As I said, I didn't manage to root the locked device.

It didn't restart into recovery and I couldn't install Superuser.

The original thread for TA backup can be found here.

STEP 6 Unlocking the device

Now that the problem of backing up the TA partition no longer exists the rest of the steps are rather easy.

Go to the Sony website to unlock your device and follow the instructions carefully.

The link on how to unlock is here.

STEP 7 Get the necessary files

You will need:

- TWRP to have recovery from here.

- The Oreo ROM from here.

- Gapps from OpenGapps. (choose ARM, 8.0 and stock)

- TA partition repair from here. Choose the Z3C version and download from Mediafire.

Download everything in one directory.

Websites where information can be found:

How to Root And Install Official TWRP Recovery For Sony Xperia Z3 Compact

Restore Lost Functionality on Your Unlocked Xperia Device

STEP 8 Putting it all together

We are almost finished.

- Connect your (running) device to your computer and copy OmniROM, SuperUser, OpenGapps and DRM Function Restore V3 to the Download directory on your device.

- Goto settings -> developer options -> switch USB debugging on (you have done this long before)

- Copy TWRPxxxx.img to your adb directory on your PC

- Find the adb directory (Minimal ADB and Fastboot), press the Shift key and right-click on the directory -> choose Open PowerShell window here.

- In the command window type <./adb devices> (without the ./ it won't work) (without the < and the> of course)

- On your Phone you have to permit adb debugging from your PC (you have done this long before)

- Device connected, positive answer on your screen

- issue the command <./adb reboot bootloader> to go into fastboot mode

- type <./fastboot devices> to see if all goes well

- type <./fastboot flash recovery twrp.img> or whatever the name of the twrp image is. twrp-3.0.2-1-z3c.img

- It takes just as sec and the screen shows its OK

- Boot up your phone by pushing vol-down and on/off together to go into recovery mode and TWRP will show.

- TWRP asks to change the system partition from read only -> Swipe to allow modification

- Choose WIPE -> Swipe to factory reset (patience)

- Go back twice (do NOT reboot) to goto the main menu and choose Install

- Goto the Download directory and choose

-> omni -> add more zips -> superuser -> add more zips -> open gapps -> add more zips -> DRM function restore

-> Swipe to confirm flash

- If you only install Omni and forget superuser and gapps you will end up with a non-system. DRM function restore is luxury.

- Wipe cache and Dalvik cache

- Automagic reboot will follow

- Unplug

- Be patient , the first boot of your Oreo loaded Z3 Compact will take a while.

Step 9 Hurray

You did it!

You ended up with a superb Z3 Compact!