We have a Buffalo NAS connected to our network but it cannot be accessed via Windows VPN. I can ping the device by IP but cannot browse to it by IP or hostname, I cannot get to its http login screen either so that eliminates any permission errors. I have ran a tracert and it as no problem seeing the device. The gateway address is correct on the NAS and the VPN connection. The only thing that seems to be a bit different is that DHCP is set up on their mail server and Routing & Remote Access is set up on their DC, I don't know why this is it was already like that before I took over. I don't see why that would be causing an issue though as both servers are on the same local network and are visible over the VPN.