您好，
关于错误代码809的问题描述，我们可以从下面链接获取更多详细信息：
http://blogs.technet.com/b/rrasblog/archive/2009/08/12/troubleshooting-common-vpn-related-errors.aspx
Error Description: 809: The network connection between your computer and the VPN server could not be established because the remote server is not responding. This could be because one of the network devices (e.g, firewalls, NAT, routers, etc)
between your computer and the remote server is not configured to allow VPN connections. Please contact your Administrator or your service provider to determine which device may be causing the problem.
Possible Cause: This error usually comes when some firewall between client and server is blocking the ports used by VPN tunnel
a> PPTP port (TCP port 1723) is blocked by a firewall/router. [Applicable to tunnel type = PPTP]
b> L2TP or IKEv2 port (UDP port 500, UDP port 4500) is blocked by a firewall/router. [Applicable to tunnel type = L2TP or IKEv2]
Possible Solution: Enable the port (as mentioned above) on firewall/router. If that is not possible, deploy SSTP based VPN tunnel on both VPN server and VPN client – that allows VPN connection across firewalls, web proxies and NAT.
注：由于没有相关的中文信息，因此只能提供相应的英文文档。
从描述来看，您的这个问题很有可能跟防火墙有关，如果VPN所需端口被防火墙禁止，就很有可能导致这种问题。建议您参考上面这个解决方案来解决您的问题。
Please remember to mark the replies as answers if they help, and unmark the answers if they provide no help. If you have feedback for TechNet Support, contact tnmff@microsoft.com.
