One of my users experiences this behaviour when he tries to create a new calendar entry. Click the “new” button, causes the client to connect to the server. In fact, any operation on the new calendar form triggers this. I compared this to another machine and it does not behave this way. On both machine, the mail database is a on a local replica and the client is connected to the server.
Sorry for the late reply. The location document showed local. I also open the database direct from the workspace to ensure it is the local replica that is being opened.