is it possible that a VPN/SSTP connection in Windows 7 is not TLS 1.1 or TLS 1.2 capable?
I deactvated the TLS 1.0 Protocol on my NPS Server (Windows Server 2012 R2 Standard), then I tried a VPN/SSTP connection to this server. During this I took a look at WireShark (on the client) and it stated that the client (Windows 7) wants to use the TLS 1.0 Protocol.
Afterwards I tried to force the TLS 1.1 and TLS 1.2 Protocol through the registry settings (SecurityProviders/SCHANNEL/Protocols)
on the Client Operating System, furthermore I deactivated the TLS 1.0 Protocol.
But it is not possible to established a VPN/SSTP connection with my Server. I have tested this whole scenario with Windows 8 Client and all things are running fine.