When executing the apt-get update command, you may get “There is no public key available” warning message. This article explains how to solve this warning message message. $ apt-get update Get:1 http://debian.linux.org.tw lenny Release.gpg [394B] Get:2 http://debian.linux.org.tw lenny Release [73.6kB] Get:3 http://debian.linux.org.tw lenny/main Packages [5310kB] Fetched 5384kB in 1m13s (73.5kB/s) Reading package lists... Done W: [...]