I'm running Ubuntu 14.04, using the i3 window manager. I'm having troubles with the Software and Updates for my system. When I start the update-manager I get this screen :

The internet is working when I see this, I'm not using a proxy.

After selecting ok (bottom right) I see this :

I select install now (from the bottom right) which just closes the screen. I then run sudo apt-get update; sudo apt-get upgrade -y just for measure, and then restart the computer. This has made no difference.

I can't select any of those radio buttons, or at least if I do select one it doesn't stay selected.

Starting from the left (Ubuntu Software) this is what I have, I can't select any of the radio buttons that are on these pages:

After selecting 'close' on the previous window I SOMETIMES the following message :

After pressing reload on that I get this error message (again, my network is fine while I'm getting this)

Here is the error message text from that :

W:GPG error: http://download.virtualbox.org trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 54422A4B98AB5139, W:Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/dists/trusty/main/binary-amd64/Packages 404 Not Found , W:Failed to fetch http://ppa.launchpad.net/jon-severinsson/ffmpeg/ubuntu/dists/trusty/main/binary-i386/Packages 404 Not Found , E:Some index files failed to download. They have been ignored, or old ones used instead.

After closing that screen I get the update manager which displays the following:

I'm not sure why these are an option when the others weren't.

I have displayed pictures of the GUI because I'm not sure how this ties in to the apt-get and such, but I'm happy to utilise any CLI methods.

Edit

Here's the output of /etc/apt/sources.list

deb cdrom:[Ubuntu 14.04 LTS _Trusty Tahr_ - Release amd64 (20140417)]/ trusty main restricted # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://archive.ubuntu.com/ubuntu trusty main restricted deb-src http://archive.ubuntu.com/ubuntu trusty multiverse restricted main #Added by software-properties ## Major bug fix updates produced after the final release of the ## distribution. ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team, and may not be under a free licence. Please satisfy yourself as to ## your rights to use the software. Also, please note that software in ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team. deb http://archive.ubuntu.com/ubuntu trusty multiverse ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. deb http://archive.ubuntu.com/ubuntu trusty-backports main restricted multiverse deb-src http://archive.ubuntu.com/ubuntu trusty-backports main restricted multiverse #Added by software-properties deb http://archive.ubuntu.com/ubuntu trusty-security main restricted deb-src http://archive.ubuntu.com/ubuntu trusty-security main multiverse restricted #Added by software-properties deb http://archive.ubuntu.com/ubuntu trusty-security multiverse ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. deb http://archive.canonical.com/ubuntu trusty partner deb-src http://archive.canonical.com/ubuntu trusty partner ## This software is not part of Ubuntu, but is offered by third-party ## developers who want to ship their latest software. deb http://extras.ubuntu.com/ubuntu trusty main deb-src http://extras.ubuntu.com/ubuntu trusty main deb http://archive.ubuntu.com/ubuntu trusty-updates multiverse restricted main deb http://download.virtualbox.org/virtualbox/debian trusty contrib

Output of apt-get update

Ign http://ppa.launchpad.net trusty InRelease Ign http://ppa.launchpad.net trusty InRelease Ign http://dl.google.com stable InRelease Ign http://ppa.launchpad.net trusty InRelease Ign http://ppa.launchpad.net trusty Release.gpg Hit http://dl.google.com stable Release.gpg Hit http://ppa.launchpad.net trusty Release.gpg Hit http://ppa.launchpad.net trusty Release.gpg Hit http://dl.google.com stable Release Ign http://ppa.launchpad.net trusty Release Hit http://ppa.launchpad.net trusty Release Hit http://dl.google.com stable/main amd64 Packages Hit http://ppa.launchpad.net trusty Release Hit http://dl.google.com stable/main i386 Packages Get:1 http://download.virtualbox.org trusty InRelease [5,637 B] Hit http://ppa.launchpad.net trusty/main amd64 Packages Hit http://ppa.launchpad.net trusty/main i386 Packages Hit http://ppa.launchpad.net trusty/main amd64 Packages Hit http://ppa.launchpad.net trusty/main i386 Packages Hit http://ppa.launchpad.net trusty/main Translation-en Ign http://download.virtualbox.org trusty InRelease Ign http://dl.google.com stable/main Translation-en_GB Ign http://dl.google.com stable/main Translation-en Ign http://download.virtualbox.org trusty/contrib amd64 Packages/DiffIndex Ign http://download.virtualbox.org trusty/contrib i386 Packages/DiffIndex Err http://ppa.launchpad.net trusty/main amd64 Packages 404 Not Found Err http://ppa.launchpad.net trusty/main i386 Packages 404 Not Found Ign http://ppa.launchpad.net trusty/main Translation-en_GB Ign http://ppa.launchpad.net trusty/main Translation-en Ign http://ppa.launchpad.net trusty/main Translation-en_GB Ign http://ppa.launchpad.net trusty/main Translation-en Hit http://download.virtualbox.org trusty/contrib amd64 Packages Hit http://download.virtualbox.org trusty/contrib i386 Packages Ign http://download.virtualbox.org trusty/contrib Translation-en_GB Ign http://download.virtualbox.org trusty/contrib Translation-en Fetched 5,637 B in 2s (2,360 B/s)

edit

I'm not sure what I'm meant to do about this error - apt-cdrom ?

W:GPG error: http://download.virtualbox.org trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 54422A4B98AB5139, W:Failed to fetch cdrom://Ubuntu 14.04 LTS _Trusty Tahr_ - Release amd64 (20140417)/dists/trusty/main/binary-amd64/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs , W:Failed to fetch cdrom://Ubuntu 14.04 LTS _Trusty Tahr_ - Release amd64 (20140417)/dists/trusty/restricted/binary-amd64/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs , W:Failed to fetch cdrom://Ubuntu 14.04 LTS _Trusty Tahr_ - Release amd64 (20140417)/dists/trusty/main/binary-i386/Packages Please use apt-cdrom to make this CD-ROM recognized by APT. apt-get update cannot be used to add new CD-ROMs , W:Failed to fetch cdrom://Ubuntu 14.04 LTS _Trusty

edit 2

I've logged in with Unity instead of i3 which has enabled me to install a few things using the update manager, as well as alter the option of Universe packages (because it prompted for a password whereas this didn't happen on i3, so the privileges weren't correct).

However I still get the Check you internet connection error when I load the Update manager (from within Unity).

Here's an error that I got after trying to reload the package information from the update manager :