Found this: "Selected folder is already added to BitTorrent Sync" If you try to add a folder to BitTorrent Sync and you see this message, it's likely that you've already used the "secret" you're entering for one of the other folders you're currently syncing. It's not possible to sync two separate folders on the same device using the same "secret". How can I release that btsync is mirroring the hard disk to hidrive?