cisco VPN client cannot connect to VPN gateway

[chuikingman]

I use cisco vpn client ver 4.6 in win XP and try to connect to VPN gateway that have public IP.

My computer is connected by direct cable to a router .And this router is connected

to internet by PPPoE .

I use Cisco VPN client ver 4.6 and try to connect VPN gateway .

But It is failure.The error is 412.

But if the same computer connect to internet by PPPoE directly and the VPN client

can connect the same VPN gateway without problem .

Why do I cannot connect VPN gateway when there is router .

How can I fix it ???

Please advice .