I have a site to site VPN setup between a remote office (3 XP Pro boxes) and HQ (SBS Server, 8 XP Pro). I happen to be using Zywall 5's, but I believe this problem is unrelated to the VPN Hardware.
HQ's network is: 10.112.12.x (SBS Server is 10.112.12.10)
Remote network is: 10.112.14.x
The Zywall is handing out DHCP on the remote network - and is handing out DNS of 10.112.12.10. The remote boxes can surf the web using the SBS DNS, but can't connect to companyweb or do /connectcomputer.
For the solution to this issue, I have seen references to adding an IP route on the SBS box, but after an hour of googling - I'm asking for help on how to do that.
I don't want to have each remote user (on the remote LAN) have to use the software VPN connector - I want them to be using a site to site VPN, so that they're not "remote users" but that they feel like they're on the network. Also - I'd like the computers on the remote network to be accessible via RWW - which also necessitates the site to site VPN.