I looked inside my battery port slot with a flashlight. Didn’t see any dirt. I swabbed inside with cotton dipped in 70% isopropyl alcohol, paying most attention to gold contact leads. Also cleaned gold terminal leads of battery. And to be sure battery was charged properly, used multimeter. It read 3.74 volts. Fully charged. Blew inside battery cavity to make sure any droplets of water evaporated away. Loaded battery, shut door and … the darn camera fired right up on first try. Perhaps slight buildup of dirt over the 5 years of using this was the problem. But DON’T GO BY CAMERA SAYING LOW BATTERY! That is a false reading, obviously, as my battery was perfectly charged. Hope this helps you guys.