I am new to VPN. I used ISA 2000 SERVER QUICK START GUIDE to install and configure ISA 2000 on Windows 2003 Server Enterprise Edition. I followed step by step guide provided to configure my VPN Server/Client. I have a DSL link at both client (my boss notebook) and VPN server (running ISA 2000)end with dynamic ip. I used DDNS service to map dynamic ips for VPN Server (our office server). Both ends have DSL modem that works as a router as well. I configured these modems, at both ends, to forward PPTP protocol.
As per recommendation in Quick Start Guide, I installed ISA 2000 on a seperate machine running Windows 2003 Server Ent Ed. with DNS service installed on it and made it a member of our local domain.It is also a DHCP server. On local domain there is a domain controller(a seperate machine) running Windows 2003 Server Ent Ed. which is also running a DNS service. I configured DNS Service on ISA Server machine as per guidelines provided in Quick Start. As per Quick Start I also used windows authentication for VPN clients.
Now, the issue is that when i try to connect a vpn client(which is not a member of a local domain)by using my administrator account of local domain, it shows that its verifying username and password but then disconnects by saying that remote computer didnot respond. Interestingly,at VPN server end, in a 3rd party tool called NETMONITOR, it shows that a connection has been established by a remote system with IP address that my VPN client is using but disconnects after few seconds.
Could someone tell me that what could be the reason that my VPN client doesnt connects.
I've had similar issues with ISA's PPTP VPN connection. My connections will disconnect with out actually tearing down the VPN connection, yet nothing is pingable. I have also had issues with the server being rebooted and ISA not binding TCP/1723 to the external interface. My research came accross an article from Microsoft that explains a simalr issue to this and it has to do with the order in which the network cards are accessed by the services on start-up.
In short, you want to open up "Network Connections" in Control Panel, Click on the Advanced Menu > Advanced. On the Adapters and Bindings tab, you want to make sure your external interface is at the top of the list.