Software updated failed

[Colin Law]

On 7 December 2012 03:32, JD <jd1008 at gmail.com> wrote:
> This is the error message:
>
> W:GPG error: http://repo.mate-desktop.org quantal InRelease: The following
> signatures couldn't be verified because the public key is not available:
> NO_PUBKEY 68980A0EA10B4DE8,
> W:GPG error: http://packages.mate-desktop.org quantal Release: The following
> signatures couldn't be verified because the public key is not available:
> NO_PUBKEY 68980A0EA10B4DE8,
> W:Failed to fetch cdrom://Ubuntu 12.04 LTS _Precise Pangolin_ - Release i386
> (20120423)/dists/precise/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 12.04 LTS _Precise Pangolin_ - Release i386
> (20120423)/dists/precise/restricted/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,
> E:Some index files failed to download. They have been ignored, or old ones
> used instead.
>
> Question is why is it looking for
> cdrom://Ubuntu 12.04 LTS _Precise Pangolin_ - Release i386
> (20120423)/dists/precise/restricted/binary-i386/Packages

In System Settings > Software Sources check that the CD is not
selected as a source in any of the tabs.

Colin