Zero-length files with 32 character hex string names: Purpose? OK to Delete?

On occasion we find one and sometimes a number of zero length files in a Vault which have filenames like D1C1AD66-0721-4A4E-9F5C-9CBA4BA3648D.

Why are these being written; do they indicate a failure of some kind; and is it OK to delete them?

(I'm NOT referring to the folders with similar names which occur in the Catalog folder.)