.blend file vanishing or unable to copy

Hi,
don’t know if this is the right thread.
I have this problem wich happened to me few times while working on 2 different projects.

Do you know synology driver (is a NAS software for server and backup)? we do use this NAS in our studio to keep projects in sync among different workstation (windows 10).
It happened that the .blend files are not copied on different machine (only with files generated by blender) - they just are in one machine and synology doesn’t sync.
This is weird and I solved the issues (it was for our last Xmas project https://vimeo.com/381198212 ) creating another folder and moving all the project files into it. Synology eventually started to sync the .blend files.

Today happend me this other weird stuff (this time no synology involved): I had to move a big folder (with severral blender project into it) to an external HD and I moved the folder into another pc (I did this way because it was pretty big and no time to sync it via synology). I opened the project on the new pc and I realized that only few .blend files have been copied among the ones I was working last friday. So now I don’t have with me the latest version of the file and cannot have access to the pc where I picked them up.
Anyway why .blend files sometime have this issue? it is just me and my network?
We work on several project with other softwares and this neve never happened to us.
Any idea? I am really scared of saving and moving blender files right now.
Thanks guys,

Andrea

Only me having this issue?