I have a Linux Mint 17 (Qiana) machine, which was updated from Linux Mint 14 to 15 to 16 to 17. Currently, apt-get update consistently fails (for several weeks now) with this error message:
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://packages.linuxmint.com qiana Release: The following signatures were invalid: BADSIG 3EE67F3D0FF405B2 Clement Lefebvre (Linux Mint Package Repository v1) <firstname.lastname@example.org> W: Failed to fetch http://packages.linuxmint.com/dists/qiana/Release W: Some index files failed to download. They have been ignored, or old ones used instead.
This happens even immediately after I follow the suggestion from this similar question:
sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com 3EE67F3D0FF405B2
What's the problem here?
I see that similar questions were closed as duplicates of "how to change my sources list" - this is not what I'm asking, I know how to edit the /etc/apt/sources.list file. If the solution is a specific change to that file, I'd love to know.
For what it's worth, these are the contents of my /etc/apt/sources.list file:
deb http://packages.linuxmint.com/ qiana main upstream import # deb http://archive.ubuntu.com/ubuntu/ trusty main restricted universe multiverse deb http://archive.ubuntu.com/ubuntu/ trusty main deb http://archive.ubuntu.com/ubuntu/ trusty-updates main restricted universe multiverse deb http://security.ubuntu.com/ubuntu/ trusty-security main restricted universe multiverse deb http://archive.canonical.com/ubuntu/ trusty partner deb http://cran.rstudio.com/bin/linux/ubuntu trusty/ # deb http://archive.getdeb.net/ubuntu trusty-getdeb apps # deb http://archive.getdeb.net/ubuntu trusty-getdeb games # deb-src http://packages.mate-desktop.org/repo/ubuntu precise main