I tried many ways to solve this problems, non of them works. Until I found this solution.
Two steps required. Before moving on, please make sure your system is Windows 7.
Step 1:
Download and install the newest driver for your wifi from here (32 bit, 64 bit) (Very important).
Step 2:
Click start, enter “cmd”, press “ctrl + shift + enter”. This allows you to open DOS under admin.
Copy paste following two commands into cmd, one by one.
netsh wlan set hostednetwork mode=allow ssid=Test key=password
netsh wlan start hostednetwork
Step 3:
Now launch your virtual router, it should work well.
Acknowledgement
http://www.istartedsomething.com/20091106/latest-intel-drivers-windows-7-virtual-wifi-support/
http://virtualrouter.codeplex.com/discussions/249696
http://chaihaoqiang.blogspot.in/2011/04/quick-to-virtual-router-could-not-be.html
Download VirtualRouter from here : http://virtualrouter.codeplex.com/releases/view/36035
If WiFi is connected and no internet access, Just open network and sharing center and take the properties of current network having a working internet connection, in sharing tab, enable sharing of internet (1st option in Win7 and Win8). 🙂