OK. I’ve run a few more experiments. I really hoped that I could keep working with my current LR catalogue just to get done a few photo jobs I have going right now, but when I imported the photos I just took, they nearly all looked like my first photo. 🙁 So, I created a temporary new catalogue just so I could get the jobs done. However, though most of the photos imported normally, one of the ones I needed gave me the “There was an error working with this photo” message and when I tried to develop anyway it said, “An unexpected end-of-file occurred.”
Then a thought came to me: what if it is the card reader at fault? We once had a card reader corrupt an entire SD card. So, I switched to the wire and imported all my “problem” photos again. They came in perfectly! Yeah! 🙂 I hope I’ve stumbled across the solution! Time will tell, I guess.
Thanks for all your help and suggestions, @buddingphotographer!
Has anyone else had such trouble with card readers?