I am at the end of my knowledge.
I can establish a tunnel connection between the client software and the router. I also can visit the router WRVS4400N from outside. But i cannot enter the LAN behind the router, no ping, no connect to the server.
i guessed there are two possibilities for the problem, one is the configuration on the router and other is QuickVPN. After I compared QuickVPN with VPN CLIENT, I found that after I installed the VPN CLIENT, there is a network adapter appearing ( see attached picture), but for QuickVPN, there is no. So, I think the QuickVPN can not work well on my PC( windows 7 and windows xp ) just because of the network adapter. It’s QuickVPN problem. Anyone can help me to solve it.