Hard Reset SAMSUNG G800HQ Galaxy S5 mini

First method:

1. Switch off your mobile phone by holding down the Power rocker for a short while.
2. Afterwards press and hold together: Volume Up + Home + Power button for a couple of seconds.
3. When the Samsung Logo appears, you can release held keys.
4. In the next step select from menu "wipe data / factory reset" using Volume buttons to navigate and Home button to confirm.
5. Choose "Yes -- delete all user data" to confirm the whole operation.
6. After that select option "reboot system now".
7. Well done! The hard reset has just been performed.

Second method:

1. Start by turninng on the device.
2. From the Home Screen go to Menu and then to Settings.
3. Tap Backup & Reset and then Factory data reset.
4. Afterwards choose Reset device.
5. To confirm your choice select Erase everything.
6. That's all.

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