NB: you will loose all your data.
- Power off the premio p500
- Press and hold power button + volume down button.
- A recovery menu will pop up, use volume buttons to scroll and power button to select.
- Scroll down and select “wipe data/factory reset”
- Scroll down to “yes”
- After the phone has finished formatting, it will return back to the recovery menu. Select “reboot system now”.