Why is there sync problem between file in browser and app on windows but not mac?

Question

Hi

My colleague has just had a quite eerie experience with SharePoint not syncing correctly.

He opened a word file first in the browser, and from there in the desktop app. The desktop app apparently was several days old (it said in the “title bar”). When he the closed it, it said it wold start syncing, and out of fear the old version would overwrite the newer one online, he canceled the syncing.

To test what would happen if he let syncing proceed as he closed the file in the app, we made a copy of the file. When we opened the copy in the app, it the showed to not be autosaving, while also being locked for editing. Both things differing from the original file.

As he uses a windows computer, and I use a mac, I tried to open the copy and everything seems normal: Autosave is on, allowed to edit, file is up to date.

Does anyone know possible reasons for why this happens to my colleagues and not me, and what we can do to avoid such occurrences in the future?

Cheers Andreas