I was trying to upgrade my Ubuntu installation to 12.10 (Quantal Quetzal), and the update manager (Muon) kept failing with error messages like: dpkg: warning: 'ldconfig' not found in PATH or not executable. dpkg: warning: 'start-stop-daemon' not found in PATH or not executable. dpkg: error: 2 expected programs not found in PATH or not executable. Note: …