I have set the preference for Dropbox to automatically load on system start-up, but it doesn't happen. I have uninstalled Dropbox and re-installed it, but Dropbox still not starting when laptop booted up; I have signed out of Dropbox and logged in again and it performed an index of all files, but it still won't open on boot-up. I have a Dell Inspiron 15 5000 series running Windows 10. Can anyone help with this?