View Full Version : [ubuntu] APT Authentication Issue

June 21st, 2008, 12:33 AM
When doing an update (which seems to happen pretty much every day) I always get an error message:

APT Authentication Issue
W: GPG error: http://archive.ubuntu.com hardy-updates Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key <ftpmaster@ubuntu.com>

Can anybody tell me what it means? What is a signing key, where does it come from, how does it get to be "invalid", and what is the practical outcome of such invalidity?