Usually with your modem or router you get a network, also called UTP, cable. It looks as on one of these pictures
When you don't have network cable present now make sure to post the Global Rules and Firewall logs.
How to post a screenshot?
To copy a screenshot of the active window push alt+print screen to copy the active window to the clipboard (pushing print screen will copy the complete window to the clipboard not just the active window). The window is now copied to the clipboard. Paste the image in any image editing program, Paint, Paint.net, the Gimp etc, and save the file as 32 bits png image.
At the forum push the reply button. Or when using the Quick reply type some text and push the preview button.
Underneath the text box click on Additional options. Push the Choose button and navigate to the file and select it. When you want to post more images click on the more attachments link.
When done typing push the Post or Preview button.