[Read] Before Unlocking your Bootloader
It has been confirmed that unlocking the bootloader will infect and damage TA partition of Xperia M and you will lose your DRM keys forever
and loose warranty too..
So it is necessary to backup your TA partition before unlocking the bootloader. After that we can always restore the TA partition and get the warranty back.
For this purpose DevShaft has created a tool that will help you backup the TA partition.So give him a thanks for his awesome work.
For more info you can check out his thread his thread
1.Download Backup TA tool (https://github.com/DevShaft/Backup-TA/tags
) thank to DevShaft after you download!!
2.Extract it and connect your device to pc normally
3.Double click and run Backup-TA.bat
4.Follow on screen procedure.
5.Do what you want backup or restore from it.
When you want to restore your TA partition make sure you are on stock kernel and rom to avoid further problems.
Note:Never restore TA partition from another similar or even a same model device cause it will hard brick yours.
Every device has its own TA partition!!!