Hard Reset HTC One Remix

First method:

1. First, turn off the phone by using the Power button.
2. Afterwards press and hold Volum Down and Power buttons together.
3. Wait for the three Andoid images.
4. When you see them, choose the Factory Reset by pressing the Volum Down to scroll andPower button to select.
5. Well done! The hard reset is done! 

Second method:

1. Turn on the phone by using the Power button. 
2. Go to Settings and then to Backup & Reset.
3. Tap Reset Phone and choose Erase All Data.
4. Tap OK to confirm the whole operation.
5. Success!

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