Syncthing with TunnelBear (VPN) on Windows: won't connect to announce, won't sync

Hi guys, my Syncthing 0.11.16 setup on two Windows 10 x64 PCs always works as expected, both on LAN and over the Internet.

But I’m experiencing issues trying to use it when I’m with TunnelBear, a VPN service I use when I travel.

  1. The “Global Discovery” was 0/2 until I whitelisted under IntelliBear. After whitelisting, it’s 1/2 as always

  2. I still cannot connect to my other remote PC (to Synthing is “disconnected”, even if I’m actually Remote desktoping it). The log always reports:

[LCNKZ] 21:43:55 INFO: TLS handshake: WSARecv tcp An existing connection was forcibly closed by the remote host.

Uhmmm, that is a IANA reserved private range, so something is definitely not right.

Any help?

Ok, whitelisting my remote PC’s IP solved the issue.

Still: I know ST is encrypted and stuff, but I’d love to use it through TunnelBear anyway. Is this possible?

This seems to be a TunnelBear thing, whatever that is. If you can establish outgoing connections, and the other side can accept then, you should be able to connect. There’s nothing fundamentally incompatible about using Syncthing inside a VPN - I do so daily.

Thanks Jacokb, I noticed that TunnelBear uses UDP for everything, even if there is an option to force TCP. Maybe this doesn’t play nice with ST?