Hi. when I plug the ethernet cable in the router

After it is plugged in, try pressing the little tiny reset button on the back with a pin or paperclip. Hold it down for 10 seconds. Make sure the ethernet is not plugged in to numbers 1-4. It should be plugged in to the single plug. Make sure your wireless card is enabled in the properties at right rear bottom of main window screen, right click on internet icon, go to properties and set up a home network with connection wizard which will guide you through the process