Is there a way for me to retrieve a file I've removed while I was in Lightroom? I had a bunch of files that said "the photo did not exist" on my hard drive - it was just in Lightroom. First of all, I don't understand that and if someone could direct me to a quick nuts and bolts explanation, I'd appreciate it! But I also need to know if I can get back one of those images that I accidentally deleted. Thank you!
You need to restore the photo from your backups.
Lightroom does not contain your photos, they only exist on your hard disk, somewhere, wherever you put it, or wherever you directed Lightroom to put it. Thus, you should never delete the photos from the hard disk. Lightroom stores the location of the photo in it's database, and when the photo is not in the location Lightroom expects it to be in, Lightroom tells you the photo is missing. Lightroom does make "previews" of the photo so it can show you the small thumbnail in the Library module. Even if you delete the photos from the hard disk, the preview is still visible in Lightroom. Once you delete the photo from Lightroom, this really means you are deleting the record in the database and the preview will also be deleted.
Got it ... thank you!