Use only one "Shared folder", check all your files and delete all the ones that are 851.7k.

Most of the people I know, they block hosts that have those files in their shared folder. I do the same thing. I know this is not good because many people are not going to be able to access my shared folder but this is a good way to keep careless people out. Careless means, people that don't clean their shared folders from those pests.
I suggest you do the same thing. Every time you search for a file and those 851.7k come up, block that host. That will remind them to clean their shared folder.