Following instructions from https://fedoraproject.org/wiki/Upgrading_Fedora_using_yum
I used yum to update from Fedora 17 to 18
su -c ‘yum update yum’
su -c ‘yum clean all’
su -c ‘yum –releasever=18 –disableplugin=presto distro-sync’
su -c ‘rpm –rebuilddb’
But afterward my LDXE Desktop was slower to start and displayed an error message:
Error initializing authority: Error calling StartServiceByName for org.freedesktop.PolicyKit1: GDBus.Error:org.freedesktop.DBus.Error.TimedOut:
Moreover, the shutdown menu showed only Logout and Cancel. It was missing the first 4 menu items including Shutdown and Reboot.
I fixed it by re-installing Policy kit…
# yum reinstall polkit\* upower
…thanks to advice from http://email@example.com/msg20483.html
This may not be an LDXE problem, but a Fedora upgrade via Yum problem.
I just learned now it is indeed a bug when using Yum to update from Fedora 17 to 18. Ref: https://bugzilla.redhat.com/show_bug.cgi?format=multiple&id=841451