PPTP连接失败，错误800/806

我有一个客户端（Server 2008 R2）不能连接到我们的生产环境PPTP VPN服务器（Server 2003，运行RRAS）。

服务器位于TCP1723打开的防火墙以及GRE之后。我们办公室的其他客户可以很好地连接。我们的办公室位于瞻博networkingSSG5-串行防火墙的后面，但是允许所有传出通信，并且多个其他客户端能够连接到VPN服务器而没有任何问题。

我还在办公室以外的另一个networking上设置了完全不同的VPN服务器。运行的客户端连接就好 – Server 2008 R2机器不。所以特别是这台机器肯定是个问题。

我重新启动了它。我已经禁用防火墙，也没有骰子。

我已经在服务器/客户端上运行PPTPSRV和PPTPCLNT，并且能够完美通信 – 表明使用TCP1723和GRE都没有问题。

服务器2008 R2机器也作为VPN服务器本身运行（传入连接），这是完美的。无论是否有活动的传入连接，我们都有问题。

我不确定我的下一个debugging步骤是什么; 有什么build议么？

编辑：服务器上的事件日志从RasMan有以下警告：

A connection between the VPN server and the VPN client xxx.xxx.xxx.xxx has been established, but the VPN connection cannot be completed. The most common cause for this is that a firewall or router between the VPN server and the VPN client is not configured to allow Generic Routing Encapsulation (GRE) packets (protocol 47). Verify that the firewalls and routers between your VPN server and the Internet allow GRE packets. Make sure the firewalls and routers on the user's network are also configured to allow GRE packets. If the problem persists, have the user contact the Internet service provider (ISP) to determine whether the ISP might be blocking GRE packets.

显然，这表明GRE是一个潜在的问题。但看到我有其他客户连接没有问题，以及PPTPSRV和PPTPCLNT能够沟通，我怀疑这可能是一个红鲱鱼。

编辑：这是客户按时间顺序logging的匿名事件：

 CoId={742CB15C-A7E0-47B7-8240-0EFA1139CBD9}: The user XXX\YYY has started dialing a VPN connection using a per-user connection profile named ZZZ. The connection settings are: Dial-in User = XXX\YYY VpnStrategy = PPTP DataEncryption = Require PrerequisiteEntry = AutoLogon = No UseRasCredentials = Yes Authentication Type = CHAP/MS-CHAPv2 Ipv4DefaultGateway = No Ipv4AddressAssignment = By Server Ipv4DNSServerAssignment = By Server Ipv6DefaultGateway = Yes Ipv6AddressAssignment = By Server Ipv6DNSServerAssignment = By Server IpDnsFlags = Register primary domain suffix IpNBTEnabled = Yes UseFlags = Private Connection ConnectOnWinlogon = No.

 CoId={742CB15C-A7E0-47B7-8240-0EFA1139CBD9}: The user XXX\YYY is trying to establish a link to the Remote Access Server for the connection named ZZZ using the following device: Server address/Phone Number = XXX.YYY.ZZZ.KKK Device = WAN Miniport (PPTP) Port = VPN3-4 MediaType = VPN.

 CoId={742CB15C-A7E0-47B7-8240-0EFA1139CBD9}: The user XXX\YYY has successfully established a link to the Remote Access Server using the following device: Server address/Phone Number = XXX.YYY.ZZZ.KKK Device = WAN Miniport (PPTP) Port = VPN3-4 MediaType = VPN.

 CoId={742CB15C-A7E0-47B7-8240-0EFA1139CBD9}: The link to the Remote Access Server has been established by user XXX\YYY.

 CoId={742CB15C-A7E0-47B7-8240-0EFA1139CBD9}: The user XXX\YYY dialed a connection named ZZZ which has failed. The error code returned on failure is 806.

在客户端上运行Wireshark将显示正在尝试并重试发送“71configuration请求” 在这里输入图像说明