Since Ubunto 13.10 muon updater doesn't work for me. To be able to update, now use gnome update-manager Reproducible: Always
"Install Updates" button never becomes active and label says "The software on this computer is up to date"
It just flashes once or twice as if a list of the packages to update were being shown, but finally nothing changes and the green shield, saying everything is up to date, stays.
this problem still remains in ver 2.1.0 also
*** This bug has been marked as a duplicate of bug 326581 ***