Hello!
I would look for a solution like the one Microsoft Office Online uses.
So if you have say an Excel file, it can be opened by 2 users at once to edit …
If one writes something in it, the other can see it.
Is there such an additional application?
Microsoft Office Online has been discarded
That is correct. For collaborative editing, they must all use ONLYOFFICE/Collabora (not both). Anyone opening the file in MS Excel locally would not be participating and would overwrite the file on save.
I’m using Office files in the desktop app, so the user opens the file directly on the PC. Is there something to block 2 files from opening simultaneously or have some warning that the file is open?