Sorry - don't have an email error sample as they are deleted after being read, and Trash has been emptied. Do remember "baseurl" being mentioned and a particular repository being unavailable with hints to try to work-around the error. The same for all ClearOS systems. Enabled automatic updates and ran /etc/cron.d/app-software-updates. Two lines were added to /var/log/system.
My script produces much more useful information...
As part of my installs always disable auto system updates - far too dangerous. Retrying later in the day got the app-base and clearos-release updates on a test system OK.