I encountered this same problem. I also killed the old btsync process and uninstalled the btsync packages in Synaptic. I found the .sync folder in the top level of the directory_root path apparently has something to do with this. My recommendation would be to delete any existing sync folders and .sync folders under your btsync directory_root in addition to the settings.dat* files in your storage_path .sync directory (this will be in the directory containing your 'btsync' executable unless you explicitely set it to point someplace else in your config). I ended up using the './btsync --dump-sample-config >btsync2.conf' command to create a config file to preset a few parameters before using './btsync --config btsync2.conf' to launch BTSync 2.0. Along the way, I also removed the .sync folder in my storage_path, which caused btsync to create a new device ID that had to be linked to my other devices. I would try this as a last resort. The current Android app doesn't let me delete the defunct desktop device. Hope this helps, Curt P.S. Note to the developers - you need better documentation and/or tools for device password recovery.