Using LR 6.14 stand alone version. My Lightroom photos and edits are on an external hard drive. To create a backup I made a copy of the entire hard drive to a new hard drive, essentially a mirror. Checking the new drive I find that I am only seeing the smart previews and not the original photos when opening LR. The photos are on the new drive but are not being seen. I'm sure it's something simple to fix but it's escaping me. Any suggestions welcomed. Thank you. This is on an iMac using Mojave if that makes any difference.
In the Folders panel, right-click one of the top-level folders and do Show Parent Folder. Keep doing that until you've got a root folder that contains all the other folders shown in the Folders panel. Right-click that root folder, do Update Folder Location, and select the copy of that folder on the new drive.