my LR catalog, previews and original photo uploads are all stored on an external hard drive, not my IMac desktop. It is now full. How do I move and back it up in its entirety to ANOTHER external hard drive without getting "?" on everything?
With everything on the external drive, all you should have to do is copy everything over to the new drive. Then double-click on the catalog on the new EHD. But even if you do get the "?", If everything is still in the same folder structure with one parent folder, it should be very easy to remedy by simply finding the missing folder.