Attempting to update my repository on our Ubuntu VPS running the gutsy 7.10 version…I noticed that I was getting 404 ERRORs caused by the distribution being moved from its normal place within the mirrors.

deb http://old-releases.ubuntu.com/ubuntu gutsy main restricted universe multiverse

replace all the URL’s with http://old-releases.ubuntu.com

you should now be able to update your packages etc from this URL.