PS I've now had another look at the synchronization process. There is no download from the web of ny photos shot with my phone or iPad. to my computer. Uploading new photos from my computer to the web works fine. Also, metadata changes on my computer seems to MOSTLY upload fine. However, there remains five images that stalls in uploading. When I remove these images from the catalogue, five new images are listed as in transfer to the web – but nothing happens. They just sit there.
I've gotten this sync error as well. In my case, it's happening in conjuction with LR cloud servers getting my meta-data mixed up across different photos. (Photos are replacing other photos and getting mixed up througuout the cloud synced photos) Adobe has been workign on my issure for months with no resolution. The ticket just keeps timing out as they provide no update then I have to create a new one. Did you get resolution? I've also recreated new catalogs but the problem lies in the cloud so it persists.