This is the comment from the manual that concerns me:
• Turn the camera off and wait for the “LUMIX” display on the LCD monitor to clear before removing the card or battery. (Otherwise, this unit may no longer operate normally and the card itself may be damaged or the recorded pictures may be lost.)
Everything else you mention I have done already. I believe it is the original battery. The camera is their water-proof, shock-proof model. I have had it about 3 years. It has not been dropped. It may have been subjected to temperature above 100 degrees but not recently. It has gotten wet many times on the outside and sometimes shows fogging inside the lens cover/window. This is normal. I am careful about cleaning the water seal. It came out of a rice-drying process when the problem occurred. Not dirt or sand inside.
I am not yet convinced it is not the battery. But I am concerned that I might have removed the battery when the Lumix screen was on and corrupted the software.
I have a new battery on order. Yes, I don't mind trying to update the firmware. Attached to W7, it shows up as an ultra fast media reader in the control panel. I can't very well go into the menu settings of the camera and change it to a camera. So let me know when you can sit down with me and try a firmware update. Give me a couple days so I can get the new battery first.
Just checked battery voltage with digital and analog VOM. Digital said 0, analog said 4.5. It should be 3.6. Still don't know if battery is any good. Now the start up beep has stopped so I can't tell when the camera is on. Either the camera is deteriorating (how?) or the battery is eating itself. Later.