In order to hard reset a HTC 8XT, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
HTC 8XT device will be brought back to the default configuration of a brand new device.
1. First of all, turn off the phone.
2. Next, hold down the Volume Down + Power buttons.
3. When HTC logo shows on screen, release the Power button
4. An exclamation mark will appear. When it does, release Volume Down and quickly press the following buttons: Volume Up, Volume Down, Power, Volume Down.
5. Congrats! Your phone will now reset and reboot, concluding the hard reset process.