Found photos after extracting previews- process to recover

[Greatwhitewing]

Having messed up and lost original files I extracted previews as an emergency work around. I have since found the original files on CD's years later.

What's the best process to replace the extracted previews with the original files without losing keywrods and edits?

All the extracted files were prefixed with "extracted-" other than that files names are the same. Below is one example directory of many hundreds of photos in dozens of directories

[dj_paige]

Is this a question about Lightroom Classic?

If so, what is an example of the file name of these photos inside of Lightroom Classic?

Are the photos you found from a long time ago the unedited original JPGs, or have they been edited?

[Rob_Cullen]

Simply replacing the extracted images with the originals (in FIle Explorer) would seem like a simple process, but unfortunately they are different File-types : JPG and DNG.  LrC would show the JPGs in the catalog as 'Missing'.

The only answer I can think of would be to Import the DNGs to the Catalog (thus you have both JPGs and DNGs in the catalog) then use a Plugin to synchronze the edits from the extracted JPGs to the original DNGs- (Later delete the JPGs)

Syncomatic – Lightroom Solutions