Question : Problem: VPN Connection thru SBC DSL

I have a Net-integrator VPN Server at office, when I try and connect thru any SBC DSL connection with any computer the VPN shows connected but I can't access anything on my network. I can connect thru dial-up or any other broadband connection and access all functions on the network without a problem. any ideas??

Answer : Problem: VPN Connection thru SBC DSL

GRE is General Router Encapsulation (IP protocol number 47). Basically the VPN traffic is encrypted and put inside a GRE packet.