For those of you who doesn’t want to play with the drivers and manually do it and use cmd now there is a simple tool called SE Bootloader Unlocking v1.6 . It basically does the same thing like the unlockbootloader site by Sony but just makes your part way easier. You just have to enter the IMEI number and you get the unlock code in an instant and then just click Unlock BL – no cmd commands required at all .You can even relock your bootloader(but I doubt you will get back your warranty) and flash new kernels too ! This software supports all Xperia 2011 and 2012 range of devices.
– Download and install Microsoft .NET Framework 2.0 to run this program!
Extract “SE Bootloader_Unlocking_Relocking_1.6.rar” and you’ll find out “Flashtool-drivers.exe”, run it to install . When installing, remember to choose drivers for fastboot and Flashmode! Just hit Install Anyway if Windows ask you to install the drivers!
– From your phone dial pad, press *#06# to get the IMEI code.
– Open the program. Enter the 14-digit IMEI code into the first text box.
– Press the Get Unlock Code button. You will see your unlock code in the Unlock Code box.
– Turn off the phone, hold Volume Up and connect the USB cable to the computer. If the LED light turn blue that means the phone is now on Fastboot mode.
– Click the Unlock BL button. The program will automatically unlock your bootloader!
– If you want to flash any custom kernel to install CWM or root your phone, double click on third text box and select your .IMG or .SIN file. Click Flash to flash the custom kernel.
– If you want to relock bootloader, click Flash Mode and then check Relock BL , double click on third text box and select your .FTF file. Turn off the phone and hold Volume Down and connect the USB cable to the computer. If the LED light turn green that means the phone is now on Flash mode. Click Flash to flash your FTF relock file.
– If you want to flash .FTF file do as above but uncheck Relock BL. We have on more Option is Wipe Data / Cache use to Factory reset when flash new firmware ! If you only need to repair your phone please don’t check Wipe Data / Cache.
SE Bootloader Unlocking v1.6:http://www.mediafire.com/?bbbuq5dcppus6lo