TCP/IP between host without LAN to VirtualPC?

I have got a Lenovo laptop that is running on Windows Vista Service Pack 1. I have also installed Virtual PC 2007 cable with Windows XP. I want to know a way to communicate between the laptop and a Virtual PC with TCP when the lan cable is not plugged. If the laptop is connected to a lan then I am able to ping the Virtual PC with XP but when I unplug the laptops lan cable then it is not possible to ping the same XP pc. Does someone has any idea how to fix this issue? Thanks

Check the below method to solve the issue:

1. First of all you need to select Edit + Settings in the menu.
2. After that you can select Networking in the list.
3. Now you have to select the host's loopback adapter instead of the physical NIC