Windows: 2.2.5 (130), Selective Sync OFF Android: 2.2.2 (376) - linked device to Windows, so it has read-write permission, configured with Selective Sync ON All the 5 .pdf files that I add on the Android become a .bts file on Windows, and they never get synced. I have not tried other file extensions. OK, so the procedure is the following: 1) On Android, I put a .pdf file inside the folder (using the file manager, not BitTorrent Sync). 2) A .bts file shows up on Windows but never gets synced. 3) The .pdf appeared on Android Sync as an unsynced file. I click the file and it is waiting to sync. 4) This file IS inside the Android folder, and I can open it using the file manager. 5) This thing happed with 3 files but now I cannot reproduce it with a fourth file. I've just created Request #34133 with Windows logs, and I've sent Android logs as well. Thanks