After upgrading to Ubuntu 13.10, my system was continually telling me that there was an update available and to run do-release-upgrade to install it. Running this command yields

root@server:/home/dlasley# do-release-upgrade
Checking for a new Ubuntu release
No new release found

but the system still prompts for an update. This is due to an issue with the Ubuntu upgrade script not setting permissions correctly. To resolve this issue, open a terminal console and enter:

sudo chmod -x /usr/lib/ubuntu-release-upgrader/release-upgrade-motd

The system will no longer prompt you to update (unless there is actually an update available)