But - when I take a new photo if I later navigate to the InstantUpload folder on the same device with which I took the photo, it can’t be displayed (big warning triangle and text saying that the photo can not be shown).
On investigation, I see that the filename exists on the device but the file size is zero.
If I delete it locally I can then get it again from the server and everything is normal.
Roger, set the app to refresh in the background and give it a day or two (pending the amount of data you have) and check back. The NC client seems to incorrectly state that the sync has finished when it has not yet completed. (at least in my experience / testing)