Using Windows 10 May 2004 edition with a brand new install of File History on two different machines now, I have managed to run into the following issue.
Selecting Clean up versions, then "Clean up":

I get the following dialog:

Again, this is on two different machines, with a clean install.
Note that I am using a simple folder with a 4KB file within it, although I first saw this on a fully-configured install with about 1.5TB worth of data within it. This led me to diagnosing the issue and ultimately trying it on these two separate machines
with a clean install.
Is this a known issue for 2004?
Thank you for any assistance/context/insight you can provide!