wireless Internet can't connect

remove the network device from the device manager, and allow the computer to rediscover it. This should reset any settings that may have been thrown off with the device.

After that I would immediately look to whatever firewall or security software you may have installed. I can't really be much more specific without the information provided.
If you need detailed instructions on getting to device manager to remove/reinstall the device just say so, it's not horribly complicated though.

Note: you may also simply disable and then enable the device using the same steps, only you would right click disable, then right click the same item again and enable though I don't know if that will reset the associated settings.

open control panel (choose small icon view in the top right if you don't already have it that way)
click system.
In the window that opens click device manager on the left side of the screen.
A new window will open.
In that window you want to look for network adapters, then click the little triangle to expand it.
If you have more than one device listed there, you may have to use a little common sense to figure out which one is the device you want to deal with. (if that doesn't work post a screenshot and someone here can tell you)
Once you've located the device right click it and choose uninstall.

If the device doesn't automatically reinstall itself you can
a - reboot, it should detect the next time you log into windows
b - right click the computer name (the very top item in the device manager window) and choose scan for hardware changes.