On the main PC where the broadband connection established go into control panel, network connections.
Select and right click on the connection, select properties.
On the sharing tab select the option to share this connection.
Now on the other PC open the control panel. network connections.
Delete any connections which exist.
Now use the wizard to make a new connection. Make sure you select the right options. If this Pc is wireless you will be prompted for the WEP/WAP key. This is the security code which needs to be entered exactly as on the HUB, usually on the base or you can find it by going into the HUB configuration. (it will be at least 12 letters/numbers long).
Finish the wizard and check the connection.