You must do this configuration on both computers:
goto network connections screen from control panel... On the sidebar there should be an option to "Setup a Home or Small Office Network" Keep clicking Next until you have to pick how your setting up your network,
- On one of the computers Pick the 1st option (if one of the comptuers has internet, choose this option on that comptuer)
- On the other computer pick the 2nd option
Keep clicking next..... After the setup finishes, just tell it to end the wizard without making a network disk or whatever.....