May i know what is the version of the Lightroom you are using and also is it a windwos computer or mac.
In the meanwhile i would recommend you to try this.
- Go to the location where your catalog is saved on the computer
- There will be a folder by the name of "Lightroom Catalog Previews.lrdata
- Drag the folder to the desktop and restart the Lightroom
- Check if the same issue reoccur
The default Lightroom catalog is stored:
Mac (user) /Pictures / Lightroom
Win (user) / My Pictures / Lightroom
If, however, you have made another catalog and have lost track of it, easiest way to find it is to select Lightroom > Catalog Settings (Mac) / Edit > Catalog Settings (Win) and click General. In the Information area, it displays the path to the currently open catalog. Click the “Show” button to reveal the catalog in the Finder (Mac) / Explorer (Win).
I use the latest CC update on Mac Yosemite 10.10.5. The catalog and image files is on a thunderbolt connected drobo 5D. Laptop basically newest, highest spec MacBook Pro.
What I did was to rebuild 1:1 previews and that solved the problem, although it took some time, which was what i wanted to work around.
Is there a way to “refresh” the current preview manually?
Do you still want me to do the steps below?
yes by dragging the "Lightroom Catalog Previews.lrdata" folder to the desktop we will manually refresh the preview.
Make sure that the Lightroom is closed when you are doing it.
As soon as the Lightroom will Launch again it will automatically will create the same folder and will create all the preview again.
but if the issue has been resolved , we don't need to do this. you can keep this for the future reference