As above. No changes to system, no program upgrades. The only thing new is that I did recently use an external hard drive to back up my computer. I have been using another external drive for almost a year as well as backing up on a Time Capsule so I can't see why adding another external drive would alter anything. Thanks for any suggestions. I've got too many photos now and have been trying to prune them back.
If you are trying to delete any image from Lightroom catalog and from your computer, please make sure that you have Read and Write permission on that particular location.
Please provide appropriate permission and check for the issue.
Let me know if this helps.