You must run a command line with admin rights.
Type in:
netsh wlan set hostednetwork mode=allow ssid="MySSID" key="Mykey" keyUsage=persistent

Leave the commanline-window open

Go to your Device Manager and check if you see a "Microsoft Virtual Wifi Miniport Adaptor" when expand the network adaptors.

If you check your wireless network cards in your network and sharing center you´ll see a second wireless network connection.

Go back to the admin-rights command shell and type in:
netsh wlan start hostednetwork


ALSO DON T FORGET TO SHARE THE INTERNET CONNECTION WITH THE CONNECTION YOU MADE!!!