I have a Debian VPS and I know about PPTP. I have followed the installation process as what is stated here: http://askubuntu.com/questions/199286/create-vpn-server-using-the-ubuntu-vps
However, when I tried to connect to this VPN with my Windows computer through Network and Sharing Center (Control Panel\Network and Internet\Network and Sharing Center), I get an error message: Error 619: A connection to the remote computer could not be established, so the port used for the connection was closed.
I have followed instructions here: 9dQ">http://www.youtube.com/watch?v=zoizPT_9dQ on how to connect using a Windows 8 computer (I am using Windows 8 now).
My credentials used are correct.