Using Classic Outlook on Windows for personal email, calendar, and contact management
The user files are stored via folder redirection to the network share and the windows sync center take care of sync documents/desktop to that personal share folders. It works like that more than 15 years and only after the last update of Microsoft Office it start to try to connect to that shares via HTTP like it's SharePoint instead or DAV instead of using the SMB protocol. So it's defined some kind of bug in the new version of Microsoft Office (new experience).