Apt-get. GPG error.
From MyWiki
I found a better way to do it that I originally thought would be the way.
So, what I wanted to fix was this: error message when I was trying to do apt-get update on a system that was quite old by then:
GPG error: http://http.us.debian.org sid Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 010908312D230C5F
To fix it I run:
gpg --keyserver subkeys.pgp.net --recv 010908312D230C5F gpg --export --armor 010908312D230C5F | apt-key add -
Then:
apt-get update
NOTE: Some people said that they had to use a different key server (for example wwwkeys.eu.pgp.net).
Or you could do this:
sudo aptitude install debian-archive-keyring