First method:

  1. Make sure, that your cell phone is on.
  2. Next tap: Menu -> Settings -> General -> Master reset.
  3. Now select an option, and follow the instructions that appear.

Second 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.
    HardReset SONY ERICSSON C905
  3. Next click "Start" under the name "Support Zone New!".
    Factory Reset SONY ERICSSON C905
  4. Wait until the process of the installation is completed.
  5. Now you should see window with in example option "Phone / Tablet Software Update".
    Master Reset SONY ERICSSON C905
  6. Accept this option -> click "start".
  7. Then click "repair my phone / tablet".
    Permanently delete data from SONY ERICSSON C905
  8. Please follow all instructions, and confirm that.
    Wipe data SONY ERICSSON C905
  9. Read "Inportant information", and confirm.
    Format SONY ERICSSON C905
  10. Afterwards PC Companion is "preparing computer for software update".
    Restore SONY ERICSSON C905
  11. Next select your phone / tablet model.
    Remove screen password SONY ERICSSON C905
  12. Follow steps, which you see in new window.
    Remove Screen Lock SONY ERICSSON C905
  13. That's all!

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

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