Originally Posted by
GrumpyDiver
You can search your computer for all image files and then copy them into a common directory; but there are some inherent risks (duplicate file names, etc). Once you have done this, you can do a single import. You will also have lost all of your edits, unless you have a backup you can restore from (this would also cover the files that you are trying to re-import into Lightroom).
I have never trusted Lightroom since the day I lost a lot of edits when the LR database (i.e. the catalog) got corrupted. I too use Photoshop and manually store ALL my image files either by year / date or by event. As I keep saying; Lightroom has a fatal flaw - its database reliant structure. All of your eggs are in one basket if you use LR in the "official" way. When I do use it, I set up a separate catalogue, buy project, to minimize this risk.
Now that you have been burnt; I suggest you look at a lower risk workflow for your future edits.