If it says that there is no internet connection and is shows network as public means that router cant give an ip adress.There are some reasons for this to happen. Try checking if windows is set to have cusom ip adress.
1.Open control panel
2.Network and sharing center
3.Change adapter settings
4.Manage Wireless Networks
5.Right click on your network
7.Double click on Internet Protocol Version 4
8.Make sire if Obtain IP address automaticly AND Obtain DNS server address automatically are checked. If not check them both.
10.Click OK again.
11. Make a restart to be sure.
Try this and if it doesnt work tell me i can give you more possible fixes.