Quite bezopasnogo and doesn't require any knowledge, much channel loading, but if I'm not mistaken there virtal in cmd it is possible to replace only old files.
1) to Let VPN (security through public channels)
2) the Program is in .bat file (well, it's just Watson)
2.1) to Delete files
2.2) Make a copy
3) set up a task scheduler, a VPN can be kept constant. (this is also very simple)