Hard Reset SONY Xperia X F5121

First method:

  1. At the very beginning hold down the Power key in order to switch off the device. Hard Reset SONY Xperia X F5121
  2. Afterwards go to Settings and then to Backup & Reset.Remove Screen Lock SONY Xperia X F5121
  3. Then selec Factory Data Reset and tap Reset Phone. Permanently delete data from SONY Xperia X F5121
  4. After that, choose Erase Everything if you are sure you want to clear all your data. 
  5. In the next step select OK to confirm the whole operation.
  6. Congratulations! The hard reset has just been performed.

Second method:

  1. First you should download PC Companion, in example from here: http://www.sonymobile.com/gb/tools/pc-companion/
  2. Install it and run.
  3. Next you will see window with 4 options.
    Master Reset SONY Xperia X F5121
  4. Choose option "Support Zone New!", and click "Start".
    Wipe data SONY Xperia X F5121
  5. Wait for the program to install the appropriate add-on.
  6. After that you will see next window with 3 options.
    Format SONY Xperia X F5121
  7. Go to option "Phone / Tablet Software Update", and click "Start".
  8. Select "repair my phone / tablet".
    HardReset SONY Xperia X F5121
  9. Now follow the instructions and accept all informations. 
    Restore SONY Xperia X F5121
    Remove screen password SONY Xperia X F5121
  10. Please be patient and wait until preparing computer for software update is complete.
    Remove Screen Lock SONY Xperia X F5121
  11. Afterwards choose your phone / tablet model.
    Permanently delete data from SONY Xperia X F5121
  12. If you see this window, then connect your device into your PC.
    Hard Reset SONY Xperia X F5121
  13. Great job! Your device is ready to use.

Third method:

  1. If the display is off, press the Power key to turn it back on.Hard Reset SONY Xperia X F5121
  2. In the next step open the phone's dialer and type in: *#*#7378423#*#*.Remove screen password SONY Xperia X F5121
  3. From the menu which should appear on the screen choose option Customization Settings and then Reset customization.
  4. Confirm information: "data will be cleared and factory data reset will perform".
  5. Accept by pressing Reset customization and reboot.
  6. Well done! You have just performed the hard reset operation

Fourth method:

  1. First of all, you should download flashtool from Sony website: http://developer.sonymobile.com/services/flash-tool/
  2. Make sure, that you have installed drivers for your USB data cable.
  3. Now turn your device off.
    Hard Reset SONY Xperia X F5121
  4. Then press and hold Volume Down, and connect to USB cable.
    HardReset SONY Xperia X F5121
  5. Follow the instructions on your screen, and accept appropriate options.
  6. Success!

Hard Reset SONY Xperia M4 Aqua - factory reset by Android settings

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

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