This is a little bit complicated. about badvpn HOT 4 CLOSED

The examples in http://code.google.com/p/badvpn/wiki/Examples apply to Windows 
too (with obvious changes like paths and not messing with user accounts), and 
are very much step-by-step. For certificates, the certutil executable is 
shipped together with the Windows build. If you don't understand how BadVPN 
works, read http://code.google.com/p/badvpn/wiki/badvpn . The meaning of 
arguments to the client and the server is explained 
http://code.google.com/p/badvpn/wiki/badvpn_server and 
http://code.google.com/p/badvpn/wiki/badvpn_client .

BadVPN was not designed as an end product for users with little knowledge about 
networks. Also, there is no GUI available. The only way to use BadVPN from 
Windows is to start it yourself, either from a shortcut, a batch file, or 
something more sophisticated.

In fact, BadVPN is really one of the simpler VPN systems. For example, it may 
appear complex because it leaves some configuration up to the user (such as 
configuring the addresses and routes); but for a skilled user, this may be 
preferable, especially when integrating the software into a larger system.

If you are still having problems, *after* you have read the documentation on 
the wiki, feel free to email me and I should be able to help.

OK, thanks.