Go to settings > Security > Mark "Unknown sources"
Settings > Developer options > Mark USB debugging
Settings > Xperia > connectivity > USB connection mode > select MSC mode
================================================== ================================================== ======================================
Ray - Kernel
All other users - Kernel or even try the kernels for Arc S and Ray
3) Run Flashtool click on the flashing icon ( left side below "file" option)
Select flashmode > ok
Setup should be like this > select OK
Follow the steps connect your mobile and flash.
Flashtool may show error after flashing kernel, no worries. Even your build number, android version won't change. Everything would remain same. So please don't go to phone settings to check anything
4) After flashing restart your device, It may not start completely, may remain at Sony logo or blank/black.
Whatever the status is, just restart your device and proceed with the rooting--->
( Make sure you close flashtool before running the rooting toolkit )
Now connect your mobile to PC and Root Your Phone
If you face problem in downloading the toolkit then here it is
1.root ur device using "andorid emulator" trick
2.install Busybox (1.18.4)
3.install SU files (ICS specific)
4.do some checks for free space, tmp directory (will remove Google Maps if required)
Before u begin:___________
1.make sure u have installed adb drivers for ur device
2.enable "USB DEBUGGING" - from (Menu\Settings\Developer Options\Development)
3.enable "UNKNOWN SOURCES" - from (Menu\Settings\Security)
4.[OPTIONAL] increase screen timeout to 10 minutes
5.connect USB cable to PHONE and then connect to PC
6.skip "PC Companion Software" prompt on device
[ WARNING ]
make sure that no other adb server is running in background (e.g.: Flashtool, PCC, SEUS) and disable any antivirus
[ How to install? ]
1.extract ALL the files in the zip
2.now just double click on "runme.bat"
3.sit back read the on screen instructions
4.the device will reboot a couple of times
5.when the script finishes it will say "ALL DONE"
5) Download 4.1.B.0.587 Kernels here (Links Below
Arc S. 587 - Kernel
Your mobile is now rooted (See if any Superuser app has been installed on your phone ) and back to life
If it's successfull
Credits goes to Androxyde, Bin4ry, Doomlord
im this post got in sony mobile