Mystery folders appear with same name as external hard drives - and they screw up access to the drives.

I have lots of photos saved on external hard drives. They are connected to my Luminar or Lightroom catalogues when the images are first imported. Occasionally I start up Lightroom and none of my photos can be accessed. When I go to reconnect an image I see in the search process a folder with the same name as my external hard drive. This folder cannot be seen in the finder so it must be invisible. But it does show up in the relinking process in Lightroom.

When I "get info" on this folder it takes a very long time trying to show the memory used by the contents but I have never seen the process complete. So I trash the folder and Lightroom once again can find the photos. When I try to open the folder no contents appear.

This has happened 3 times with 4 different hard drives.

Does this indicate some sort of hack being done on my computer or is there another explanation?

What causes these folders to appear. If it is a hack how can I prevent it?