I store my catalog on a dropbox file directory that syncs to several computers. Consequently, there have been multiple instances where conflicts have occurred with the catalog being opened on both machines. Dropbox will usually create a copy of the catalog with a modified name to accommodate the catalog being open on two machines. Inevitably, lightroom will create a new previews file (.lrdata) for the catalog.
I have since become a hawk about not ever opening the catalog on both machines at the same time. But I am now stuck with a bunch of .lrdata preview files that I am afraid to delete in case they pertain to my main catalog in some way. My files end up looking like this.
The current catalog is called "_All Photos of all time_Current.lrcat" I am wondering which of these preview files I can delete.
In reality, you can delete any or all of them, and it won't affect the work you have done. Lightroom will just begin creating a new set of previews as you work in Lightroom.
The ones with the blue icon were still updating to dropbox when you made this screen grab, so those are the most current. The locate_lock file should automatically delete itself when you quit Lightroom.