I did this by accident tonight and had to restore and reconfigure a bunch of stuff. DOH!

Hard Reset HTC Hero Android : HTC Hero Reset Procedure | DIGITAL BITS: "Hard Reset HTC Hero Android Phone – Procedure Trick


1) Turn off your HTC Hero completely.

2) Keep pressing the HOME key and Back key together for some while.

3) While pressing the Home and Back button, once press the power button.

4) Wait for a few seconds and you get a message on the screen asking for a confirm reset.

5) Now release the Home and back buttons press Menu.

6) Your HTC phone is now reset to its original state.

During this process, if your phone hangs, just remove the battery and try this procedure again. It definitely works."