Wired Connection won't work

Everytime I try to connect my xbox via a wired connection it will not work but I can use wireless perfectly fine.. I have horrible connection using wifi while i'm upstairs which is why I want to use wired. I used to play on wired all the time with my old PS3 and stuff but with this XBOX One I can't.... The wierd thing though is that when I check it while it's wired it says "All services available" but when I click "Test network connection" it says "Xbox cannont resolve DNS server names" Can anyone help?