I have been testing BitTorrent Sync as a backup solution for a while, and it has not been flawless. Today I spent some time to research the problems, and I found that the problem was on my setup and not in BitTorrent Sync.
The problem
Occasionally BitTorrent Sync stops syncing and reports “Error: BitTorrent Sync cannot identify the the destination folder”.
The cause
My Images folder (Bilder in swedish) was actually synced I yet another step. This is my setup:
BitTorrent Sync will maintain control files in each synced folder named .SyncID and .SyncIgnore.
My first Robocopy sync was of course deleting the .SyncID file from the source folder of the BitTorrent Sync.
The solution
The easiest way to fix this is to add the control files to the “real” source folder, for me the Laptop. Another option would be to add an exception in the Robocopy syncronization to make sure the control files are untouched.
The credits
This is the forum post that pointed me in the right direction:
http://forum.bittorrent.com/topic/24602-bittorrent-sync-cannot-identify-the-destination-folder/