KB3024777 has been described as the 'silver bullet' to sort out problems with KB3004393 but it hasn't worked for me yet. IT has failed to install fourteen times.
I've posted in the Microsoft Community here: http://answers.microsoft.com/en-us/windows/forum/windows_7-windows_update/kb3024777-has-failed-to-install-fourteen-times/348bb50b-245a-4d08-9964-6887503fd2eb?lc=2057&auth=1
I haven't resolved it yet but am getting closer!