Hard Reset HTC Touch Diamond2 (HTC Topaz)

1. Turn the device off using Power button. 
2. Press and hold both Volume rockers. 
3. Briefly press the Power button, 1 to 1.5 sec.
4. Don't stop holding down the Volume buttons.
5. Then pressing Volume Up key will Factory reset your device.
6. Factory reset can take a while, mostly several minutes.

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