vpn issue

I need help please. Can’t get VPN to work. I have a home pc and a labtop both xp pro.I have dsl from bellsouth.I have done the steps about 10x.When i’m setting up both xp’s for client and server I get no errors, things seem to be fine.But when I tryto access the IP frm the client I get error 800.Also for the users if I look at properties there’s already a password in there and i can’t change it.Tyred setting up a new user but still the same issue on the server.