Thanks both for the replies to this question. I've found the answer, so worth posting here to help others. I also have two outstanding questions.
It seems like two of the photo files had some kind of error/corruption. When you try to create a shared album using a batch of photos containing these two photos, the whole process fails. But there is no error message. A shared album is created, but it doesn't contain any photos.
I discovered this because I tried to create the album I wanted to share in a number of ways. The last method I tried was to manually add the photos to the shared album in small batches (say a dozen at a time). All the batches added to the shared album immediately, except for those containing the two corrupted files. When I tried to add those batches, I got an error message: "There was an error adding the selected items to 'shared album test'’". I was then able to isolate the corrupted files by adding one photo at a time (and only tow photos generated the error message)
My hyphothesis therefore is:
- If a photo file is corrupted, it won't add to a shared album and causes all photos in the batch you are trying to add to fail
- If you try to do this by selecting all the required photos from the library (or from a non-shared album) and creating a shared album with these photos, the process fails but there is no error message.
- If you try to do this manually by selecting and then moving photos to the empty shared album, you do receive an error message when you try to add the corrupted photos (or the batch containing them).
My remaining concerns are:
1) How can you tell that a particular photo has a corruption/error? They behave as normal when viewed in the library or in an album (non-shared). The problem here is that
2) What kind of corruption would this be and how prevalent might it be (i.e. how many photos might experience this)?
