Sometimes it seems to happen that the lock-file is not automatically deleted when LR closes. A lock-file prevents that the catalog is changed by any other program while LR is open (with this catalog).

Try the following:

Close LR. In your OS navigate to the location where you found your catalog that you want to open. Do you see any files with the ending <lrcat.lock> ?

Delete this file. It should not be present when LR is not open, but should be present when it is open.

Then just double-click the .lrcat file and LR should open with this catalog.

WW

If there was no such file while LR was open then LR was open with a different catalog.

I can't really answer your question regarding you rkeywords but am assuming that Lr doesn't use the catalog you worked with last before you formatted your HD.

You have to find this catalog. If you can't find it you have to re-assign your keywords to your photos.

You can check which catalog LR is currently using. Go >Edit > Catalog Settings >General Tab. You will find the name and location of the currently used catalog there.

WW

When individual images (a few but not all within a folder) are missing in the Grid View click the question mark on the frame of the images and navigate to the correct location of the image on your hard drive.

If a question mark appears besides a folder in the folders panel right-click this folder and <Update Folder Location>, i.e. navigate to the correct location of the folder on your hard drive.

Do this for the uppermost folder in the hierarchy that show question marks and all the sub-folders will be found by LR too, provided that the folder structure itself and the folder names have not changed.

The question marks not only appear when you moved images / folders outside of LR via your OS but also when you rename folders / images outside of LR.

All these things, moving images / folders, renamaming images / folders are best done within LR. That way LR keeps track of the new location / the new name.

WW

I'm not quite sure what you mean by "editing".

If you mean organizing your images and folders and renaming them, the YES you best do this in LR and don't do anything outside of LR. You have to understand that LR is not a file browser. A file browser program "sees" whatever is on the hard drive. You move and/or rename a file in your OS, the file browser program will "see" the changed file name in the new location. LR on the contrary functions as a data base, called the "catalog". Only LR can read and write to and from the catalog, no other program can do that. If you change ("edit") your images in another program there will be a discrepancy between the LR catalog and the new situation on your hard drive. Then you need to fix this discrepancy.

It seems your situation was created exactly by doing "editing" in another program. This is best avoided completely.

LR is capable of doing everything you want to do. Make it your only "editor" to avoid grief and hassle in the future.

WW

It seems you have two different catalogs, one for your images on your C-drive and one for you rimages on your external hard drive.

I don't know if you have a valid reason for this, but let me tell you that it is not necessary. In fact, it is much better to have all images in ONE catalog. I have images on several internal and external hard drives and they are all in one catalog. That makes things easy and simple.

To merge your two catalogs into one import one catalog into the other via >File > Import from catalog. BUT before you do anything to your catalogs, it is a good idea to backup your existing catalog(s).

Also, there is a lot of help for LR on the web. I can recommend the videos that Adobe has put on its website; also see here: http://www.lightroomqueen.com/

WW