Setting up a VPN in Server 2008 using two NICs

Have you looked here?

http://social.technet.microsoft.com/Forums/en-US/windowsserver2008r2networking/thread/3adbd27d-29a3-412a-a8bc-cc359ae7a8ca/

I've looked at the article, but it doesn't really give me a step-by-step install guide. Thank you though.

Thank you Erik. That's the kind of article I was looking for. I will try this tonight and post my reply asap.

Your welcome

I setup everything according to the support article; however, I am not able to connect from any computer outside of the network. I am able to connect to the VPN from the local area network, but not externally. I am using a Linksys router and I do have port 1723 forwarding to the 2008 Server, as well as PPTP passthrough enabled. Any suggestions?

What is the lan side address of the PC you are attempting to connect to? Is the remote PC attempting to connect to it have an Ip address on the same subnet? If so, that has to be changed since the Linksys will think its a connection coming from the local lan and cannot find said device.

Other than that, it may be a simple NAT issue. Let us know.

The 2008 Server is on a 192.168.1.1 network, and the remote computer is on a 192.168.2.1 network. I made sure to make them different before I setup the VPN. Thanks

Can you post the exact model of your Linksys and the current firmware version for us please? Thanks in advance.

Sure. The Linksys Router is a Wireless-G Broadband Router with SpeedBooster   WRT54GS
Firmware Version: v1.52.8  

Is the local server using a firewall? Have you either disabled it or placed an exception in the rules for it? Otherwise, follow the link below and verify your settings.

http://www6.nohold.net/Cisco2/ukp.aspx?pid=96&vw=1&articleid=4594

Hope this helps.

I have disabled the firewall, and made sure that the exception is in place. Neither has resolved the issue. Also, the Linksys router does not have a VPN Tunnel option, only passthrough selections, which are all enabled. What else could be blocking an outside connection? As I said before, LAN connections to the VPN work just fine. It's the outside connections that aren't working.

I would first update your firmware on the linksys. This should allow for more options for tunneling(however, I caution this as you will need the model and exact version number of you router which can be found on the underside of the device and if you choose to do so, please do it from a PC that has a WIRED connection and not wireless). Secondly, ensure both ends are using the same encryption settings and they are attempting to access this server using your ACTUAL wan Ip address.

Ok. I am not onsite right now, so I can't check for the exact hardware version of the router. Where can I check the encryption settings? And I think it could be a problem with NAT. Where can I make sure that the VPN pool is excluded from NAT rules?

After doing some further research on this(and your given firmware version) if you are using a v5 or 6 device you may be out of luck as there seems to be a bug when using PPTP. After you check your model/version of your device and compare your current firmware with the one currently available for download from:
http://homesupport.cisco.com/en-us/support/routers/WRT54GS/download

if they are the same then you are stuck with this bug in the code. There seems to be an issue with v5 > on those devices and the firmware available. As an alternative you can go and review open source codes available to achieve your intended use without having to purchase another router at:
http://www.dd-wrt.com
I've heard nothing but great reviews but its only a suggestion. You are advised to do so by your own choice as this voids any Linksys device warranty if one actually still exists. Just a suggestion.

I checked the hardware version of the Linksys WRT54GS router, and it's version 6. We are already running the latest firmware version 1.52.8. I plan on installing another Linksys router, version WRT54G, to see if I can get the VPN working through that one. I'll keep you posted on my results.

Sorry for the delayed reply. I am installing the other router early next week. I was not able to take down the Internet connection for their office. One thing though: Is there anything I should be checking on the Client side to make sure that everything is setup properly to connect to the VPN? I am using Windows XP and Windows 7 built-in VPN connection client to make the connection.

Do you have a dmz option on your router to put your server on?
It may allow to to get past the pptp issues

I put the Server on the DMZ, but I was still not able to make the VPN connection to Server 2008. I receive an error 800 on the client side. Is something not setup right on the Server now?

I followed the article that you sent at first:

http://www.thomasmaurer.ch/2010/10/how-to-install-vpn-on-windows-server-2008-r2/

One question though. What do they mean by this in the article?
Add secondary IP Address to the Server network interface which is in the same subnet as this pool.

OK. So I was able to make a VPN connection to the 2008 Server (I had to make sure that the encryption settings matched between the Server and the client side). Thank you for all of the help.