It’s ok to drag a few files within the LR Library but for large numbers of files it’s recommended that you:
- Copy files to new drive
- Update folder location links
- Delete from internal drive
See this useful link for more information - Part 2 - Updating Folder Location
I got a new LaCie hard drive today, plugged it in and started a new folder on the drive to store my photos. In Lightroom I dragged my first folder, one which contained about 2,000 images, onto the new folder on the external drive. It began transferring files, but stopped after 532 files and said that everything was transferred. The remaining ~1500 photos seem to have disappeared - they are not showing up on my laptop nor on the external drive. Could someone help me walk through this and figure out what happened to my photos? Did I transfer the wrong way?
You have run into a rare but persistent and nasty bug that Adobe claims they have looked for and can't find (see reply 27 here: Re: The lost photos )
In the future, you would be wise to not move photos inside of Lightroom. Instead, you could move the photos in your operating system and then reconnect in Lightroom via Adobe Lightroom - Find moved or missing files and folders;
For now, you need to restore the photos from your backups.
Hey Adobe people, maybe you should look into this again.