You've had a bunch of answers, not sure if this is of value. The problem is cultural. You will not shift that. I infer Windows. Create a scheduled task that

You've had a bunch of answers, not sure if this is of value. The problem is cultural. You will not shift that. I infer Windows. Create a scheduled task that starts frequently but not if another instance is running. The task runs a powershell script. The script creates a FileSystemWatcher tracking the "HEAD" spreadsheet. On write, it copies the file, appending a date-time. Users do nothing in particular. But they visibly see backups being created. So they know they can just work on the current file and not rename it. This is horrific macguyver shit, but it's attuned to the customer needs, can be distributed as a single file that creates the scheduled task, and requires near-zero user behaviour modification. Avenues of further development: debounce, so 14 saves in a single minute don't create 14 backups; toast notifications using BurntToast so that errors are not silent