I think it might be fixed...
I tried the first link which explains how to change a registry value regarding autoplay. When I did that, my registry key already contained that value so I changed it back to the default value and rebooted. Still no change, so I went to the registry and changed it back to what it was (the value that the link tells you to change it to). Then I rebooted and now it seems to work with both my thumb drive and camera.
Time will tell if it keeps working that way.
Thanks for your help! Much appreciated