I tried a lot of things. I use BitTorrent Sync on OSX and two Android devices. The network connection works and also worked when I tried it, the only thing I did was saving a file with an application where the file was inside the syncing folder. I just reset/redid my config just now. And it seems to work now. But I didn't do anything different except from not turning off the notification icon on Android. Also a temporary disconnect from the network shouldn't be resulting in a situation that I have to sync manually, or should it? Two additions, I just got the message again. Also it wasn't all, just one device which went "offline", the device was online and connected all the time. But the sync setting disappeared from the Sync register in the Android app for a short but visible while. This is very confusing.