I work on a iMac (OS X Yosemite) in Lightroom CC and try to publish a large book to Blurb. Halfway the upload, I get this "internal error" message : "?:0 attempt to index a nil value". All I can do is cancel the upload as nothing moves anymore.. any solution to publish my book ?
I am running Lightroom Classic CC and was attempting to export 200 photographs to SMug MUG when I got this error. "An internal error has occurred: ?:0: attempt to index a nul value. I am running on Windows 10 with ALL updates applied. I have had this several times in past. Not sure of exact steps to create but will note them in future.
I finally figured out what my issue was after getting the "internal error...nil value" error message. I uploaded to Smugmug in batches of five until I hit a group of problematic images. Looking carefully at the metadata of that group, seemed I had multiple images with 0 MP file size. Thumbnail was there, but no data. No idea why. I then went through and deleted those images and restarted the upload. Everything worked seamlessly! I've now set my view options in LR to show MP size so I can easily scan a group of photos for this issue.