Okay. As an example; I have a photo I took months ago, it is stored in a folder on my hard drive. I imported it into LR months ago, worked on it & placed it in a new folder within LR.
Months later I am about to import a new photo into LR from a different folder on my hard drive, but it is greyed out as LR thinks it is a duplicate. How can this be?!
I then begin to diagnose the situation.
I first look for the file name of the new photo in 'All Photographs' within LR, & to my surprise, there it is, amongst the batch of photos imported & worked on months ago, replacing the original photo that was there, but, exhibiting all of the treatment I worked into the original months ago.
How has this happened?
There are several files I have with the same confliction.