Hard Reset HTC One

First method:

  1. Power off the device by pressing Power button.
    Factory Reset HTC One
  2. Then hold Volume Down + Power button until you see three Android images.
    Hard Reset HTC One
  3. Now select option "FACTORY RESET" to browse use Volume Down, and to choose option Power button. Format HTC One
  4. Device will reboot itself.

Second method:

  1. Go to Settings, next tap Backup & reset.
  2. Select Reset phone.
  3. if u want delete all data (all the media) select Erase all data.
  4. Press OK.

Htc One hard reset

Htc One S hard reset

Htc One X hard reset

How to Hard Reset HTC One - Full Reset in HTC

Hard Reset HTC One - How to Delete Password and Pattern

Hard Reset HTC One - How to Format HTC One

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

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