Hi,I am using LR CC and I have enountered this weird problem (I noticed it happend also in LR5 when I was using it).
After I import photos (I use standard-auto or 1:1 previews) I edit them and when I am finished I try to export them as a catalogue for further use. The export runs flawlessly but at the end of the export there is an error window saying: "Photo previews could not be found" with the file names listed. Usually it means all the photos exported to the catalogue. Then when I try to view the photos again I have to wait because photos are "loading" as if there were no previews for them. It usually happens the other day - not the same day when I import photos. As if LR "forgot" his previews overnight or something like that. Very weird is that it happens almost all the time but not for all photos - usually there are a few that obviously has previews still available (I do not have to wait when I want to view them). When I create the previews again (Library - Previews - Build standard previews) the problem is gone but next day after export it happens again.
I do not remove / rename / change any photos / folders / filenames / disk drives. Everything stays the same and the photos are there. I do have 30GB on my system drive as a LR Cache.
LR keeps losing previews somehow and I do not have any idea why is this happening. And it is very very very frustrating. For example I work on a 300 photos one day and when I want to keep editing them the other day then I have to wait to view each other image because the previews get lost and LR obviously has to create them again. Today it happend right after I imported 30 more photos to the catalogue (different photos, different folder, nothing common). The previews for the previous import (which I was working on in the morning without any problem) got lost (just a few of them remained there).
Can anybody please help me? I am paying LR / PS subscription so I would really like this to work properly.
I'm facing the same error; please help us, Adobe!
I'm using Lightroom CC as well and my client is running into the same error when she is exporting a smart previews catalog, "Photo previews could not be found (59)." What causes this error and how do we fix the problem quickly? We are, of course, under a tight deadline. Thanks!