Method 1 for ubuntu vpn connection. install VPN Client # sudo apt-get install pptp-linux 2. install network manager support for VPN # sudo apt-get install network-manager-pptp 3. add a VPN connection right-click the Network icon on the panel-> VPN connection-> Configure VPN click "add" to select the default pptp vpn connection type, and click "CREATE" to get the connection name. Enter the gateway, user name, and password, click "advanced", deselect "EAP" in "permit the following authentication methods", and select "use point-to-point encryption (MPPE) "www.2cto.com" is required. Otherwise, the connection fails. OK, save 4. select the created VPN connection to connect to the private network. Use ifconfig to view the connection. An additional ppp0 network interface is displayed. if you want to access the Internet, you need to manually add the route add-net 192.168.0.0 netmask 255.255.255.0 gw 192.168.0.1. Suppose 192.168.0.1 is the gateway. This is what I did. I am using greenvpn. Now I am a wireless network, and there is no prompt. It cannot be a school. In the same way, I can use win7.