No need to worry. It simply means the PC has a network card installed that is not currently being used, so it shows an annoying icon with a red cross in the system-tray. my laptop has the same annoyance, or at least it did until I disabled that particular network connection, which removes the icon from the system tray. You can do the same. It won't do any harm. Right click the unused connection in your network connections folder. Select 'Disable'. The system tray icon will now disappear. If you ever need to use the network card in future, simply go back in to your Network Connections folder, right-click the connection and select 'Enable' before you try to use it. You could, of course, simply leave things as they are if you can live with the unused icon in the system tray. Either way, I can assure you nothing is wrong.