I have just recently installed a new router for my home and the ethernet connection stopped showing up. It instead said "no connections available". I figured the onboard network adapter gave out because of the orange light it gave off and bought a NetGear GA311 network adapter. I installed it and updated it, but the connection still says there are none available.
Is the router also the DHCP server? Is the other computer connected the same way as yours? If the other computer is connected through an Ethernet cable, does yours work if you connect it to the same cable?