I am having some trouble with an 871w. Currently I have no firewall configured, I am using NAT. The router is connected to a residential cable modem. The issue I am having is that a client of mine is unable to connect to his work VPN from a PC behind the 871. I try to connect to my work VPN (windows as the client software) and I am able to create a connection but the dialog box will not pass the "Verifying Username and Password" portion. If I connect directly to the modem bypassing the router I have no trouble loging into the VPN. The router is blocking something. I assume it must have somthing to do with NAT. Any ideas?