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What is the easiest way to resolve apt-get BADSIG GPG errors?
Some days ago my apt-get update has suddenly began to throw
W: GPG error: http://extras.ubuntu.com oneiric Release: The following signatures were invalid: BADSIG 16126D3A3E5C1192 Ubuntu Extras Archive Automatic Signing Key
As far as I understand, this is about a brand Ubuntu repository, not something I've added (actually I were not adding any repositories and/or changing apt settings those days). How to fix this? The OS is XUbuntu 11.10 "Oneric Ocelot" x86.
I've tried
sudo apt-key adv --recv-keys --keyserver keyserver.ubuntu.com 16126D3A3E5C1192
and
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 3E5C1192
neither seems to help.
