Can’t export files and Persistent "Unknown" / "I/O Error" when saving Metadata

 

·         Adobe Lightroom Classic 15.0.1

·         .CR3 raw files from Canon R3 (firmware 2.0.0)

·         Computer spec;

·         MSI Z790 Gaming Pro WiFi Motherboard

·         Intel Core i9 13900F (Socket LGA 1700) 3.0GHz 24 Core CPU

·         Corsair Vengeance 32Gb DDR5 RGB 6GHz

·         Gigabyte Nvidia RTX4090 OC 24GB Triple Fan

·         Cooler Master Gold 1250W Power Supply

·         Cooler Master MasterLiquid ML360 Illusion Water AIO

·         Windows 11 Pro (all updates complete, including via WinGet)

 

As part of my usual workflow I let LRC export XMP files from my raws because I’ve been bitten in the past by catalogue corruption, so by writing XMP’s next to the raw files I can simply pick up where I left off with a new catalogue.

 

It all started as usual, and off a shoot I imported 761 raw images of which I picked ~180. I went through those and edited them up. All looked ok and I saw that XMP files were associated with all of the CR3’s. All good so far.

 

The problem;

When I completed the edits and tried exporting as JPG’s, LRC’s progress bar went all the way over to the right and stopped immediately. I had to close and re-open LRC, and then I tried different things in the Export box like; removing the JPEGmini plugin, removing metadata, setting different compression levels, exporting as different formats (including , etc but nothing worked, the progress bar still stopped immediately.

 

So, I tried to cut my losses with that catalogue and I made a new, clean catalogue with a different name and re-imported the CR3 and XMP files. But only a handful of the thumbnails contained the edits so I tried editing and exporting again but had exactly the same issue.

This was now a new one on me, I’ve not seen this problem before. I wasn’t sure what to do so I re-downloaded the CR3’s directly from the camera and tried again. Same issue.

 

I tried to save the Metadata from files (CTRL-S) but it gave me an “unknown” I/O error, and also an I/O error 184.

So, to troubleshoot all of this, I did the following;

·         Reset LRC preferences

·         Turned off GPU acceleration

·         Turned off “Generate Previews in Parallel”

·         Created a new Catalogue on a physically different drive (all drives are internal, one NVMe, 2x SSD SATA, 1x “standard” HD SATA)

·         Running tests on the hard drive (CHKDSK etc) and checking the S.M.A.R.T. status of the drives with Samsung Magician and CrystalDiskInfo

·         Checking and toggling the Read Only Attribute on the files and folder, I also checked File Permissions on the files & folder

·         I tried disabling Anti-Virus, and noted that Ransomware Protection is off

·         I used the Resource Monitor to see if anything else (OneDrive or backup software for example had a handle / lock on the raw files but there were none.

·         LRC was uninstalled, and I used the Adobe Creative Cloud Cleaner Tool app to completely remove all CS & CC applications, then installed fresh versions of Creative Cloud and, of course, LRC and Photoshop

·         I ran all of the CR3’s through Adobe’s Raw > DNG converter, there were no errors, and the DNG’s successfully imported into Lightroom, but crucially I could edit them and export just fine!

·         I then tried various ‘hacks’ to get the edits in the XMP files applied to the DNG’s but nothing I tried worked – even editing the XMP and removing all reference to CR3 files, just nothing worked.

·         I looked in the LRC Backup folder but there are no Catalogue backups since May (even though it does a backup once a week), and I also checked the “Previous versions” tab on the folder which the photos are in but it is empty

 I am loathed to call Adobe support as they will point their finger at the Canon CR3 files, and Canon would just as quickly point their finger at Lightroom Classic. So at this stage I’m going to bite the bullet and re-edit all the photos from DNG’s. But it still doesn’t explain why this is happening – if the CR3’s were corrupt then I the DNG converter wouldn’t work. So I’m baffled, and I’ve spent hours on troubleshooting already as you can see. I think that the only thing that has changed recently is the camera firmware but I’m not even sure it can be rolled back.