I have an iMac. Last night Apple had me erase my operating system and reinstall it. I have an external hard drive and did a back up just before we did that. Everything was there. Now that my computer is back up and running, I reinstalled Lightroom and am having trouble with the catalogs. Of course when I reinstalled Lightroom, it created a new catalog but I went back to my latest LIGHTROOM back up, double clicked and it seemed to pull up my previous catalog with some files missing. How do I recover those files? It's like they're there but. I'm attaching a screen shot.
May i know did you backed up the folders for the images which you imported inside the Lightroom.?
Yes, they were backed up via time machine on and external hard drive.
Copy the images folders to your hard drive and link the folder back with the Lightroom catalog.
Check the below mentioned help document for help.