I have been having this issue for about one year and every time I talk to support they try something that never works so I often gave up and found workarounds.
On a macbook air M1 running latest Mac OS.
In a nutshell the issue is:
1. Import raw photos from camera into Lihtroom Classic
2. Create collection with photos and share with lightroom mobile (cloud)
3. Edit photos on iPad and edits most of the time sync back to Lightroom Classic
4. However, if I add a photo in the same collection from the iPad or from the browser, the photo never syncs back up to Lightroom Classic
5. Have spent already around 20 hours either chatting or on the phone with support and they have made the issue worse in a different way
6. One agent after many hours playing around through remote access determined that the catalog must be corrupted, even though tere were no errors on any logs about it
7. They createda new catalog and were supposed to copy the old catalog but the new catalog did not show my two external hard drives on the left pane
8. Agent said to first wait for the sync of new catalog to complete which took 5 days! (around 34K photos).
9. Sync finished today and I added a photo to a collection on Lightroom Mobile on the browser nad it successfully synced back to Lightroom Classic. Then connected with an agent and they made some chagnes on settings trying to find a way to get the hard drives and the hirearchy of the files to show up on the left pane. The changes started dumping files into downloads folder and somewhere else which i haven't been able to identify
10. Agent said it was end of their shift so left. Connected with another agent and this one did File.Import from another catalog and selected the two external drives and proceeded with the import.
11. Since it was taking hours they lef and said to wait. A few hours after that Lightroom crashes and give an error from photo bleow. Basically lightroom started saving photos on the downloads folder and the computer ran out of space!
12. New agent unchecks the sync photos to download folder (not sure why a previous agent even did this!)
13. Repeat step to continue importong from another catalog. LIghtroom does same and cmputer crashed and I started deleting photos from the download folder.
In the meantime I was told five days ago to avoid using LIghtroom on the iPad becayse the sync from Classic was going on so had to use Capture One instead!
Tomorrow a manager is supposed to call but I'm exploring options on giving up and migrating to abotgher software.
If anyone has any suggestions, that would be great.
Thanks!
Jon
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