How to Solve “The following signatures were invalid: BADSIG” Error in Ubuntu Updates

It’s been a long time since I had connected my Ubuntu notebook to Internet. As a result when I connected it to internet after two weeks of gap, as all of us know that Ubuntu is quite fond of providing updates on a regular basis, I was expecting loads of updates to be provided by Ubuntu.

I typed the following commands in terminal in attempt to update the system.

sudo apt-get clean 
sudo apt-get update 
sudo apt-get upgrade

The “clean” command did nothing.

The sudo apt-get update command came up with an error:

Reading package lists... Done
W: A error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://extras.ubuntu.com oneiric Release: The following signatures were invalid: BADSIG 16126D3A3E5C1192 Ubuntu Extras Archive Automatic Signing Key <ftpmaster@ubuntu.com>
 
W: A error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://archive.canonical.com oneiric Release: The following signatures were invalid: BADSIG 40976EAF437D05B5 Ubuntu Archive Automatic Signing Key <ftpmaster@ubuntu.com>
 
W: GPG error: http://ppa.launchpad.net oneiric Release: The following signatures were invalid: BADSIG E0319082F37F3AB0 Launchpad fixes for aprsd
W: GPG error: http://ppa.launchpad.net oneiric Release: The following signatures were invalid: BADSIG 73AD8184264CE9C6 Launchpad PPA for Simon Schneegans
W: GPG error: http://ppa.launchpad.net oneiric Release: The following signatures were invalid: BADSIG DFB844B8BB91632D Launchpad PPA for Weather Indicator Team
W: A error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://ppa.launchpad.net oneiric Release: The following signatures were invalid: BADSIG C2518248EEA14886 Launchpad VLC
 
W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/oneiric/Release  
 
W: Failed to fetch http://archive.canonical.com/ubuntu/dists/oneiric/Release  
 
W: Failed to fetch http://ppa.launchpad.net/webupd8team/gnome3/ubuntu/dists/oneiric/Release  
 
W: Some index files failed to download. They have been ignored, or old ones used instead.

Did you notice the last few lines? Those are the crucial ones and we need to focus on it. It says:

W: A error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://extras.ubuntu.com oneiric Release: The following signatures were invalid: BADSIG 16126D3A3E5C1192 Ubuntu Extras Archive Automatic Signing Key <ftpmaster@ubuntu.com>

That is our culprit here: Invalid signature error BADSIG.

To remove the bad signature error, open the terminal (Ctrl+Alt+T) and use the commands given below one by one:

sudo apt-get clean 
cd /var/lib/apt 
sudo mv lists lists.old 
sudo mkdir -p lists/partial 
sudo apt-get clean 
sudo apt-get update

After using these commands you should get rid of the errors and your Update Manager should be working fine.

Still got problem? Do tell me if you still facing difficulties with the BADSIG or Ubuntu Update Manger. I would like to help you out. Keep in touch by subscribing to the newsletter. Enjoy :)

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