cant get my winxp vpn working - help!

[Crunch It Now]

ok - i have 2 winxp pro boxes, one running a vpn pptp server and one being the vpn client. when hooked on the local lan, the vpn works totally fine. however, when i try to connect through the internet into my vpn server, it will connect to the point of "verifying username and password" then it just hangs and eventually times out, giving me an error message that the remote computer did not respond. nothing in the event viewers gives my any more info.

my vpn server is on a dsl line, behind a cisco 675 running nat - ive opened everything up in the 675 and am forwarding everything to the vpn server.

i was thinking that maybe the xp vpn doesnt work across nat, but then why would it connect at all and try to 'verify username and password'? this is really stumping me, and i would appreciate any help i can get!

[Jeffbx]

Yes, it is the NAT that is messing you up.

I've done this setup a few times, and every time I end up pulling my hair out - it's a b*tch to get configured correctly. You have to set up static routes on the VPN server so the traffic knows how to get back to the client. When a machine is NATted, you can send a request to it with no problem, but the response can't find its way back through your router. (That's why you can connect to it, but it won't authenticate.)

Since you're using a Cisco router, you can program the router to send the request back out, but don't ask me how to do that - you're going to have to find someone that knows more about routers than I do...

Your other option (that I usually end up doing) is using a live IP address for the VPN server, if you have one available.