Unlock Bootloader - how to

I am not Responsible if it BRICK YOUR PHONE!

1.You must have stock rom ( orginal rom from SE)2.Check Manufactoring date/code (behind batery)     
-if yo have 11W29 above  STOP     
-11W28 below  u can try unlock bootloader
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Let's Go

1. Download 
   + S1tool http://www.mediafire.com/?iwnjno9hirpgcm1
      + Unlocker  http://www.multiupload.nl/WMHJCMO38H

2. 
a) Unzip all downloaded files
b) Shut Down Phone
c) Open S1tool, Click on DO JOB, Press Back on phone, Connect it to PC.
d) Look For Line "XXXX SIMLOCK CERTIFICATE"

3. Unlock

• Turn the phone on, Connect it with PC in Debugging mode.
• if XXXX is "NOT RECOGNIZED" then sorry, it can't be unlocked
• if XXXX is SEMC then run "msm7227_semc.cmd"
• if "XXXX SIMLOCK CERTIFICATE" was not found then run "msm7227_Setool2.cmd"
• Wait...if "Press any key to continue . . ." is found, press any key. 

4. Check unlock

• Shut Down Phone
• Open S1tool, Click on DO JOB, Press Back on phone, Connect it to PC.
• Look For Line RUNNING S1_EROM VER "x8A029"
• if x is "r" then it is done, Congrats...
• if x is "R" then Sorry, Do everything again. 

Hard brick warning - read before boot loader unlock

The phones affected by the problem are units being manufactured at, and after, 11W29!


To check if your device is affected by the problem follow this simple steps:

1. Turn off the phone and open it up
2. Take out the battery
3. Look at the sticker below

If the date code on the sticker reads 11W29, or any later date (11W30, 11W31, 11W32, 11W33, ...), DO NOT attempt to unlock the boot loader.


These phones ship with a revamped chipset configuration having the security hole the boot loader unlock uses effectively closed. This means that upon unlocking the boot loader your phone will end up as a hard brick - and you will have NO means to revive the phone yourselves. You either have to send it off to Sony Ericsson for repair (recommended solution) or find a phone repair shop being able to resurrect shot devices!


The symptom you will experience when unlocking the boot loader on an affected device is like this:

• The boot loader unlock will most likely go through fine
• At restart the phone will show NO signs of life anymore.
  NO LED, NO LCD output, NO vibration.

This is the point where you can not do anything anymore yourself to resurrect the device.


You have been warned, DO NOT TRY to unlock the boot loader on phones manufactured PAST 11W29!


source: http://forum.xda-developers.com