In order to hard reset a HTC Magic, you should perform the following steps.
Remember! Hard reset will delete all the data on your device; pictures, contacts, messages, apps and more.
HTC Magic device will be brought back to the default configuration of a brand new device.
1. Lets get started. Begin by pressing the Power button to turn your phone on.
2. Now press and hold the Back and Home buttons for five seconds.
3. Press, for a second, Power button, and then the Home + Back buttons again.
4. Please release the buttons when an Android image appears on-screen. Hold the Trackball.
5. The phone will now reset and restart, meaning that the hard reset process is complete.