Resetting you HTC X8 smartphone will return it to the state it was first time when you turn on.
Warning! All data on phone memory like (photos, videos, contacts, messages, and call history) will be erased by using this method. So take backup before reset device to factory settings.
1. Turn off HTC 8X
2. Press and hold Power Button until LCD show Htc logo. Then press Volume Down until mobile shows exclamation mark (!) icon.
3. Release all byttons.
4. Press step by step one by one.
5. Press and Release Volume Up Button
6. Press and Release Volume Down Button
7. Press and Release Power Button
8. Press and Release Volume Down Down
9. If the step finish, the HTC 8X will do the hard reset or factory format by itself.
10. Wait until it finish to format, then we will need to setup like new again.