I recently transitioned our VPN server from a Windows Server '03 box to '08 R2, both using built-in Routing and Remote Access for PPTP connections. Our firewall has a rule that forwards traffic from a public IP address (which the clients connect to) to the VPN server which is on a private subnet.
Is there an option in RRAS to force the clients to use the VPN connection for both our private and public (on which the firewall is routing traffic) subnets? VPN connections currently only have access to the private subnet unless "Use default gateway on remote network" or "Send all traffic over VPN connection" is checked on the client.
Ideally clients would route only their traffic for our private and public subnets though their VPN connection, and everything else as normal. I could have sworn we had a option set to allow this when our VPN server was on a Server '03 box.
There is no way to push routes from a PPTP server, they need to be configured on the client side. For more information, see my answer to this other question:
Windows remote access server (PPTP) advertised routes