[reggoboy]

This screen shot is just to demonstrate my typical use case where I search for a song and it finds multiple transcriptions in different jazz books. As expected, each one I tap on brings up a unique image. This list includes the two PDFs shown in the file conflict screen shots previously posted.

Mike, thanks for the reply!

That means it is seeing multiple songs with the same titles and underlying files in the library, and it doesn't know how to pick the right one.... The best way to resolve conflicts is populate the song ID fields if you are going to have multiple songs that have the same title and file

So Mike, the screenshots I shared show different PDFs, right? But you are saying the error indicates "the same titles and underlying files in the library". 

This also can occur when songs use multiple files.

I don't think I've done this anywhere, certainly not on purpose. Just individual PDFs and CSV-indexed PDFs. 

When you say:

 you should be able to verify it pretty easily by editing a few of the songs that were shown as conflicts. 

 
what do you mean by editing? Changing metadata? Annotations? And then what, try the sync again and the software should stop seeing the two as being the same "song"? 

I can email you a link to a backup of the library (it's all "internal" on macOS) and also the Sync to Cloud folder. Curious what you will find!