Reimported my folder, but all files are 1610x1080 jpgs.

[Matthew24834585fena]

I have imported original files from my hard drive into Lightroom, after reinstalling thr older version of LR (11.3) due to the new version 11v3.1 not working properly. 

i reimported all of my photos from my folders on windows, and while some have the NEF files and JPG - most have been imported as JPGS with 1610x1080 resolution in library and develop mode. 

A lot of files that were imported are greyed out as well but have the NEF format meta data. 

I have no clue on what to do here and why this happened. Please help 

[TheDigitalDog]

Check (and maybe make a screen capture and share here), your import dialog settings. 

[Willi Adelberger]

If you had converted them to a newer dng the older version might not recognize them.

[JohanElzenga]

There is absolutely no reason to reimport anything if you downgrade from Lightroom Classic 11.3.1 to 11.3. All your images should still be catalogued and both versions use the same catalog. So please explain in more detail what you did and why you did that. This sounds like you may actually have imported something like a preview.

[dj_paige]

For your future benefit, NEVER RE-IMPORT photos. This is never necessary and causes bad things to happen.

As far as your present situation is concerned, you have imported JPGs, that's the only way photos wind up as JPGs in the catalog. You need to find the catalog you were using, and open that, rather than re-importing. Then you can find the photos in that catalog (NEFs, probably) and you should be good.

[Matthew24834585fena]

Where else can I search for missing catalogs because are not catalogs to choose from? When LR updated, my catalogs never came back.

[Matthew24834585fena]

No catalogs*

[dj_paige]

In Lightroom Classic, try File->Open Recent

If that doesn't find the catalog you want, then in your operating system's search feature, do a search for all files on all disk(s) whose name ends with .LRCAT and then double-click on each one found to open it, until you find the catalog you want.