LR no longer recognizing photos/folders on HD

[BG_Phillips]

So, I have a 2TB external HD that I've been using for all my images for 2016. All have been imported into Lightroom. For 2017, I bought another (larger) external HD and I COPIED (not moved) all of the 2016 images/folders into the newer external HD as a backup. So, the original RAW files are still on the 2016 HD, unchanged, but now when I open LR to edit or view those photos, it no longer recognizes them as being there, forcing me to re-import them (thus losing all of my editing changes on thousands of photos). I can understand why LR would not recognize the images if I had moved them, but I didn't. I merely copied them to another drive, while leaving the original drive untouched. So why does LR no longer recognize the images on that drive? Using LR CC. I use one catalog for everything.

[F. McLion]

Are you on Mac or Windows?

Does the new drive have a different drive letter or mounting point?

Adobe Lightroom - Find moved or missing files and folders

[dj_paige]

Importing is totally the wrong thing to do and has made the problem worse. If I were you, I would delete the newly imported versions of your photos from Lightroom, but not from the hard disk, to get back to where you were previously. IMPORTANT CONCEPT: Never re-import photos.

The link given above by McLion is the way to fix the problem; alternatively you can fix the drive letter/drive name problem that caused this; if you are on Windows, all you hve to do is set the drive letter of the old external HD back to the letter it was previously.

[BG_Phillips]

I don't recall what the drive letter was previously (I'm on Windows), but currently the new HD I bought for 2017 photos is labled F: while the one I had the problem with is named G: Perhaps Windows re-named the drive letter on its own? I haven't had this issue come up before and I have multiple external hard drives that I will plug in via the USB ports, depending on which selection of older images I'm trying to access at any given time. I went ahead and re-imported these prior to these answers being posted. I can live with that, as most of them have been saved as JPEGs after the editing changes. It's just that I've lost the editing changes to the RAW/DNG files. Not sure how to reverse my current import... Thanks for the response. I will have to watch this for any future hard drives that I use.

[amas2]

Do not use driveletters for external drives in Lightroom - to avoid such problems use drivepaths.

[F. McLion]

If a letter is actively used from a connected drive and you add another drive Windows picks the next letter and keeps using this letter for this drive even if a 'lower' letter is 'free' next time the very same drive is connected.

If you want the new drive to use the same letter as the old you must not connect the new one the first time when the old is connected as well. If you did (probably to copy the data), you can change the drive letter anytime later using disk management (Windows + R, then type diskmgmt.msc).

[dj_paige]

BG Phillips wrote:

I don't recall what the drive letter was previously (I'm on Windows)

Lightroom will tell you what drive letter it thinks the photos are on, this is what you want to change the drive letter back to.