I've just realised that the same, or something similar, has happened to me! Just 2 machines syncing, my W7 laptop and my W7 storage server, both in my LAN, both running v. 1.3.109. I've just realised that a huge number of files on my laptop have been moved into the .syncArchive. They're now syncing back from the server -- but why is anything being synced when the files have not been touched, many of them for years even? This is 30-odd GB of copying to and fro, just for fun... And to cap it all, I now see that a couple of hours work of Friday last week is gone... I guess that was it with BTSync until I read something positive. Great program otherwise - if only it fulfilled its primary purpose :-(