Hard Reset SONY Xperia SL LT26ii

First method:

1. Press Power button until your phone is on.
   
2. Next goto Settings -> Backup & reset -> Factory Data Reset -> Reset Phone -> Erase everything.
3. Confirm that operation.
4. Done!

Second method:

1. Download program named flashtool from Sony website:http://developer.sonymobile.com/services/flash-tool/
2. Then check, that you have installed drivers for your USB data cable.
3. Now turn off your handset.
   
4. Afterwards press and hold Volume Down, and connect to USB cable.
   
5. Accept all informations.
6. The end.

Third method:

1. Switch off your phone.
   
2. Then hold and press together Power button + Volume Up + Camera key for about few seconds, or until you see menu of your screen.
   
3. After that you will see Factory reset menu.
4. Now you should from this menu choose option Erase everything.
5. Finish!

Fourth method:

1. You should first download and install program PC Companion.
   * In example from here: http://www.sonymobile.com/gb/tools/pc-companion/
2. If all went well, you will see window with 4 options.
   
3. Next click "Start" under the name "Support Zone New!".
   
4. Wait until the process of the installation is completed.
5. Now you should see window with in example option "Phone / Tablet Software Update".
   
6. Accept this option -> click "start".
7. Then click "repair my phone / tablet".
   
8. Please follow all instructions, and confirm that.
   
9. Read "Inportant information", and confirm.
   
10. Afterwards PC Companion is "preparing computer for software update".
    
11. Next select your phone / tablet model.
    
12. Follow steps, which you see in new window.
    
13. That's all!

WARNING !
Hard Reset will erase all of your data
All described operations you are doing at your own risk.