If you have the device plugged in, unplug it. Remove the back cover, pull the battery, wait 20 seconds, replace the battery, replace the cover and hold down the power key. You're device should turn on to the same red light and bolt thingy. Plug it into a WALL charger until the default clock appears and then unplug it again. This should bring you to your home screen. Turn the device off and plug it back in until it's fully charged. This just happened to my wife's Bold and it's working again.
I hope that this helps!