When I type 'sudo apt update' in a terminal, and some updates are available a suitable icon appear in the System Tray, when I click on it, discover launches but when I click on 'Update all' I got the error: "Failed to check for authentication: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: Action org.freedesktop.packagekit.system-update is not registered" Whereas when discover is launched from a terminal, after clicking on 'uddate all' button I get: QObject::connect: No such signal OrgFreedesktopPackageKitTransactionInterface::Message(uint,QString) in /build/packagekit-qt-tCxzqI/packagekit-qt-0.9.5/src/transaction.cpp:122 QObject::connect: No such signal OrgFreedesktopPackageKitTransactionInterface::Message(uint,QString) in /build/packagekit-qt-tCxzqI/packagekit-qt-0.9.5/src/transaction.cpp:122 Error happened 48 "Failed to check for authentication: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: Action org.freedesktop.packagekit.system-update is not registered" no packages for "NoMachine Server Status" no packages for "Master PDF Editor 4" no packages for "Skanlite" no packages for "OpenJDK Java 8 Policy Tool" no packages for "NoMachine Server Status" no packages for "KWrite" no packages for "VL812 B2 Firmware" no packages for "Calligra Sheets" no packages for "Calligra Words" no packages for "Info Centre" no packages for "NoMachine" no packages for "NoMachine Server Status" no packages for "VL811 Firmware" no packages for "GNU Octave" no packages for "Rival SteelSeries" no packages for "Krita" no packages for "Okular" no packages for "VL812 Firmware" no packages for "VL811+ Firmware" no packages for "Karbon" no packages for "KSysGuard" no packages for "NoMachine" no packages for "UEFI Updates" no packages for "NoMachine" needed... 1520 qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible" qrc:/qml/ApplicationDelegate.qml:79:17: QML Text: Binding loop detected for property "visible"
Please make sure your system is set up properly. The error is very suspicious...