I have got an SGP521 device.
Bootloader already unlocked by the key obtained from Sony Mobile.
I tried to install the Advance Stock Kernel with Recovery v03 (FW:17.1.1.A.0.402} by the method described uder [ how to flash this kernel ] (via fastboot).
It resulted no any errors.
I tried to follow the Rooting Instructions () but I was not able to go to Recovery mode and install SuperSU.
It could be my misstake that before I started the process the system was updated to Android 4.4.4 and I did not realize that it could affect the method.
Is there any solution to get my device rooted?
Thanks for all answers.
Thanks to the Administrators, Developers and all Members.