SoftEther VPN User Forum

What do I have to do if I had chose "Password Authentication" when I created a user Profile?
Do I need additional a certificate for a VPN type like "SSTP" connection?
Or is a password authentication enough?

No.
You'll need the certificate of the server.
It has to be imported into the computer context store (not the users one) of the client machine.

Than login name and password are working fine.