Quick tutorial for unlocking & relocking the bootloader of the Xperia S/P/U/Sola.
this is the official way to unlock bootloader
This procedure will wipe the /data partition of your phone, so you will loose all ur stored data, settings. SDCARD will NOT BE WIPED!!!
DRM keys WILL be lost forever
why to unlock bootloader?
u can flash custom ROMs/Kernels
u dont need to worry if the new firmware can be rooted or not as with unlocked bootloader u can always ROOT ur device
SE/Sony gives sneak-peaks/preview builds of latest OS which requires unlocked bootloaders, as they did with Xperia 2011 line (they had ICS alpha/beta), so who knows may be SE/Sony may give early builds of ICS (JellyBean???)
At the bottom click 'Start Unlocking the Bootloader'
First, you should confirm that it is possible to unlock the boot loader of your phone by checking the service menu. In your phone, open the dialler and enter *#*#7378423#*#* to access the service menu.
In your phone, tap Service info > Configuration > Rooting Status. If Bootloader unlock allowed says Yes, then you can continue with the next step. If it says No, or if the status is missing, your device cannot be unlocked.
after u have verified that u can unlock bootloader, scroll to the bottom of the page and click "Continue"
you will get "are u sure prompt" accept it by clicking "yes i am sure" (i assume that u have read an understood it)
then accept the "legal terms"
finally u will get a "Create Unlock request" page, enter your IMEI (sometimes the last digit needs to be removed for this to work), name and email address
You should now receive your unique unlock key, its displayed on screen, SAVE THIS KEY SAFELY
Extract fastboot_with_Android_USB_file.rar and open fastboot folder
Hold SHIFT and right click on the background of the folder
Select 'Open command window here'
Connect your phone in fastboot mode (turn phone off, hold Volume UP button and plug in USB Cable) [make sure drivers are installed as explained above)
In the cmd windows type in fastboot.exe -i 0x0fce getvar version
If a value is returned (it will return 0.5), it means the phone is correctly connected
Type in fastboot.exe -i 0x0fce oem unlock 0xKEY and replace KEY with the key which u received earlier.
Well I hope not nothing's gonna happen to the phone when we are gonna update the phone to the ICS, right now I'm in China and it's not released over here and looking forward to get this baby in my hand.
when official ICS is out, it can be flashed via flashtool as FTF file when it will be online somewhere
PS: after unlocking bootloader via official method (official Sony website way), u wont be able to update phone's software via PC Companion / or over the air
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