Draytek Vigor Failing VPN Connection
We have a Draytek Vigor 2820, which we use for remote access.
This has been working without issue for about a year, when using a Win 7 client to access. The Vigor itself has been configured with a remote VPN account.
Within the last few weeks this has stopped working with the following error:
0x800B0109: A certificate chain processed, but terminated in a root certificate which is not trusted by the trust provider.
Event Viewer essentially shows the same thing, with a source of "RasSstp".
Googling points me to this MSKB article, but it doesn't give any detail on how to spot a problem certificate (I can't see any certificate issued by Draytek): How to troubleshoot Secure Socket Tunneling Protocol (SSTP)-based connection failures in Windows Server 2008
Anyone got any ideas on how to troubleshoot this? It's almost as if a certificate was issued by the Vigor, and has now expired.