From LinuxBSDos.com.Because of licensing reasons, the Fedora project only ships Free Software applications with any Fedora release. To gain access to those applications that are not available in their repository (repo), you’ll have to enable third-party repositories.
There are any number of such repos that you can enable. The recommended ones to install are RPM Fusion and rpm.livna.org.
Now that most mirrors are dropping CentOS-4, if remaining users still need to access yum repos then edit /etc/yum.repos.d/CentOS-Base.repo, comment out mirrorlist directives, and in each ena... [by pschaff]
I have this problem every time I upgrade to a newer version. I just upgraded to 12.10, and the upgrade disabled some of my repos. I tried to enable them by just rechecking them in Software Sources, but it's still not reading them. How do I enable them???