1. Connect the iphone to the computer and then turn it OFF.2. Push the power button for 2 seconds, then (without letting go), push the HOME button as well (the one with the square).3. Keep holding BOTH for 10 seconds, then release the POWER button only (keep holding the HOME button).4. After another 10 seconds, release the HOME button. The screen should be blank.Run iTunes, and restore the iphone. This will erase everything, including the password, and re-enable it.