The Forum Lounge is not for technical help, please provide the name of the program you are using so your message may be moved to the correct program forum
Please post the name of the program you use so a Moderator may move this message to the correct program forum
This forum is not about help with programs... a program would be Photoshop or Dreamweaver or Muse or ???
The program I was referring to in my original post is Lightroom.
Based on multiple reportings in this forum, the moving of large number of files in LR on a Mac seems to be more problematic than it should be.
The rule of thumb that many of us use is this:
For a few files, drag and drop in LR works fine.
For large number of file, like a whole directory or directory tree, use Mac Finder or Windows Explorer to move/copy the files, then in LR's Folder panel, point it to the new location.
While this will prevent the problem in the future, it does not help with your missing (deleted) files now. From what I understand of the problem, the images that were on your hard drive are gone. For these missing files, you just need to restore them from a backup, then use the "find missing folder" procedure.