Unidentified Network; No Network Access - Powerline Adapters

Today, I managed to redecorate my bedroom; where my computer sat on top of a shaky, wooden desk. That desk is now gone, caput, and replaced by a much bigger, sturdier and prettier glass replacement.Before I dissasembled the computer to re-decorate, I was able to browse the internet at ease. There were no problems at all...However, after the new desk was setup - and all wires replaced in their correct slots, I find that I am unable to connect to the internet, or even the house's network! For the past year, I have been wired to the router using a RTL8168C(P)/8111C(P) Family PCI-E Gigabit Ethernet NIC. It was plugged into an extension cord, in my room, into the Ethernet port in the back of my computer. Downstairs, it's twin was situated no less than 2 feet away from the router - plugged into the first port.Now, when I boot up the computer, the network notification presents the following message: "Unidentified Network. No network access", and sometimes presents a yellow ! next to it. So, I am reduced to typing on my mother's laptop - which has no problems connecting to the network.I am able to use the ipconfig /release command, but unable to use the /renew - it hangs in the command prompt, then tells me that the DHCP server cannot be located. The IP, beforehand, was reverted to 169.254.223.117 - before all of this, I was 192.168.0.5?