File Management: LR, Windows 10, local and ext HD, missing files are not

And if your problem is during import, Have you tried not telling it to ignore duplicates?

Side, note, that documents folder, whats with all the temp files?

I read that other's rec adding the files from the onset to the ext HD, but that slows me way down when adding the files but more importantly when I edit them... Probably related to my older HP Spectre laptop (though it was pretty fast)

Photos on an external HD do not cause slowness in the Develop Module. Slowness in the develop module is caused by other hardware (but not the speed of the disk or speed of the connection to the disk) or software limitations.

SO, for the NEW problem..... I purchased a NEW HP spectre laptop w/ increased video graphics abilities. I moved all my folders/files/presets over from the old one...it's never perfect but ultimately I have the new HP running like the old one. BUT now LR doesn't recognize all the files that were on the old C:.... they also don't recognize the files on the 1 T HD finally, they don't recognize the files on the 3 T HD.... I've looked for ways to reassociate them, synch them, find them but to no avail....

Earlier you have said you know how to re-link the files after an operating system move. The same method applies here. In the Folder Panel, there should be a question mark on the folders; right-click and select Find Missing Folder and then point LR to the new location of the folder.

OLD problems: I have multiple SD chips and EHDs (ie 3 noted above) that I use.... I've never understood how LR labels the HDs. I've learned that the 3Ts were S; and T: I've seen multiple drive designations for the SD chips and other EHD (small 1 T). There's been a recommendation to "relabel" the drive so that LR will recognize the "previous location" of the files.... for whatever reason I don't know how to do that (in windows)....

You might be discussing the drive LETTER assigned by Windows (not a "label"). If the photos were on drive E: previously and are now on drive F: (or any other combination of letters) you can again use the re-link method in LR to point LR to the photos on the new drive.

along the way during the years some files have been corrupted meaning I see the file, the picture is mostly there, but there is bizarre colors or lines or other defects that prevent me from using the file... I've had to "manually" go back and search on the 3T HDs for the individual files.....slow and painful.. is there a way to synch an older folder w/ image files from the earliest 3 T (and presumable non corrupted files) ? Does anyone have a 3rd party backup/compare software to allow me to compare the two 3 Ts and make a manual decision about which files to keep/synch/disregard/delete?

If the file is corrupted and you see the bizarre colors, then the only thing you can do is find the photo's backup (by file name) and then copy the backup to the folder where the original was (thereby overwriting the corrupted original with the hopefully not-corrupted backup). This is done in your operating system.

Regarding permissions, I don't think any of your symptoms are permissions problems.

Now, nit to conflict issues by working out more than one issue or a component of an issue at a time.

Assuming the answer to the just previous is yes, LR works for new photos.

the old images on the old computer, nit the backups or extra copies on external storage, but your old primary images.

how did you copy/move them to the new laptop

where did you place them (file structure), same folder as where new photos are stored? Seperate folder?

the new Lightroom install on the new laptop. Except for old images, does it work? Can you import new photos, edit metadata in library module, post process in develop module, export to say TIFF or JPEG, etc?

Close all apps, logout of windows, log back in but as the local administrator. Using File Explorer, navigate to your drives, to the file folders your catalog(s) and images are in, look at the properties (right click, ...) look at the security settings (security tab), make sue System, your account, Administrators group, has full rights, Users Group less.