Question: I am trying to connect to a Windows based SSTP VPN network. I am using OS X Yosemite, I was wondering if there is any solution that can allow me to connect to a SSTP based VPN. 

For the record, I have already tried using EasyVPN, iSSTP, iSSTP2. all of which failed to connect, and they all seem to be not supported anymore.

Answer: 
Please check my answer here - <https://stackoverflow.com/questions/40590806/windows-sstp-vpn-connect-from-mac/40590807#40590807>

There I explained how I connect Mac to Windows SSTP (probably threads should be merged)
I think you will find [Tunnelblick](https://tunnelblick.net/%20%22Tunnelblick) will do it without any problems. It's well supported and has good documentation on the site.