Created attachment 89472 [details]
output of gpk-update-viewer -v
Debian GNU/Linux testing (jessie), gnome-packagekit 3.8.2-4, GNOME 3 GUI.
Steps to reproduce:
(1) Start Software Update tool (/usr/bin/gpk-update-viewer). It shows there are some updates available.
(2) Click "Install updates". It asks for user authentication.
(3) The following error is displayed and no updates installed:
Failed to process request.
Cannot download packages whilst offline
The output of "gpk-update-viewer -v" in in the attachment.
The Internet connection is fine. Also, installation with apt-get update/upgrade/install works fine.
I've found that Bug 30119 has a recent patch regarding this.
After some research I'd say that this is probably caused by two factors:
(1) The patch that fixed Bug 30119. It makes the aptcc backend check the status of network connectivity as reported by NetworkManager.
(2) If there are some network interfaces defined in /etc/network/interfaces the NetworkManager does not manage them by default, as of Debian 6.0. In that case it reports that there are no network connectivity (see https://wiki.debian.org/NetworkManager).
In my case the network interface settings were specified in /etc/network/interfaces.
The issue was solved by putting managed=true in /etc/NetworkManager/NetworkManager.conf so that NetworkManager also handles that interface:
$ cat /etc/NetworkManager/NetworkManager.conf
After that Software Update works as expected.
I have this problem, too. It is pretty surprising for a normal desktop user. Why is the status "resolved invalid"? I have used the software update feature already at least two times. Only today that error appears, so something must have been broken in the last update.
Debian Jessie w/ KDE. Amd64.
I marked this bug as "resolved invalid" because the Software Update actually works as designed: it reports "Cannot download packages whilst offline" because the Network Manager reports that there is no network connectivity.
In my case the Network Manager reported no connectivity because I manually configured the network interface in /etc/network/interfaces which made the Network Manager refuse to handle that network interface until I changed the default option in /etc/NetworkManager/NetworkManager.conf as explained above.