Re: Size, it's possible that a Mac and a Windows machine archived them differently, I guess. Or there are forgotten files in one.

It's an ancient computer quirk, created by lazy nerds.

It stems from the question of whether a kilobyte is 1000 bytes or 1024 bytes.

Windows and Macs use different answers.

The difference can also lead to discrepancies when viewing the same file on different operating systems. Unlike Windows machines, Mac OS shows memory capacity using the digital version of GB (and has since the Snow Leopard release in 2009).

This is especially important if you’re sharing files. A user who receives a file from a Mac to their Windows machine will see a drop in file weight, which can raise concerns about the integrity of the file transfer. The user might think the file was corrupted during transit or some sort of compression was applied which is a hard no when sharing high-resolution files (e.g RAW video files).

In reality, there is no corruption or compression, and there’s nothing wrong with the file transfer tool.

https://massive.io/blog/gb-vs-gib-whats-the-difference/#gb-vs-gib-the-confusion-persists

The Windows link is .eml files, which are Outlook files.

The Mac link appears to be in PDF format.