Ok, here's my update finally: As mentioned above I did a complete sync of a folder from my laptop to an empty folder on the raspberry (ruling out problems of recognizing preseeded files). ------------------ On the laptop Windows XP folder information lists: 20370 files / 1690 folders BTSync Client recognizes: 20353 files so there are 17 missing even though everything in .SyncIgnore is commented out ------------------ On the raspberry "find -type f | wc -l" and "find -type d | wc -l" lists: 18496 files / folders 1586 folders Interestingly the btsync web interface on the raspberry lists yet another number: 18478 files ------------------ I tried to rule out issues of weird characters but a) files with characters such as "ß", "ö", "_" are transferred and b ) also synced fine in a small test folder. Even though there are no transfers taking place anymore the sync obviously is not finished: BTSync on laptop reports "U: 40GB", on the raspberry web interface "uparrow 37.2GB". I let it sit for a few days but no activity has taken place. So there seem to be a number of issues: a) btsync client does not recognize all files and does not report which ones are problematic b ) not all recognized files are synced c) syncing stops without any information about what's wrong I hope this information will be of use to anyone in nailing down the problem. Thanks for taking the time to look into this!