all thumbnail grey - lightroom Classic

thank you for the reply.

I ended up restoring for a previous backup and this resolved the issue. it seemed that the file must have been corrupted during the upgrade process. now it all works as it should again. 🤩

I don't think this is caused by a defective monitor profile.

The three little circles on your thumbnails indicate a corrupted preview cache, which contains the Library previews.

With LrC closed, go to the folder that contains the catalog, and delete the file whose name ends with Previews.lrdata

Do not delete anything anything else.

When you launch LrC, it will rebuild the previews as you browse folders in Library.

https://www.lightroomqueen.com/how-do-i-change-my-monitor-profile-to-check-whether-its-corrupted/

With regard to your import problem, please show us a screen capture of the ENTIRE Import dialog box.