Solve "The following signatures were invalid: BADSIG" in Ubuntu

We have discussed several Ubuntu update errors in past such as Problem With MergeList, Failed to download repository information Check your Internet connection.

In this post, we will discuss another very common problem that occurs when users upgrade or update their system. This error is “BADSIG” error which looks something like this:

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 precise Release: The following signatures were invalid: BADSIG 16126D3A3E5C1192 Ubuntu Extras Archive Automatic Signing Key

W: GPG error: http://ppa.launchpad.net precise Release:

The following signatures were invalid: BADSIG 4C1CBC1B69B0E2F4 Launchpad PPA for Jonathan French W: Failed to fetch http://extras.ubuntu.com/ubuntu/dists/precise/Release

Solution to BADSIG error:

To solve this BADSIG error in Ubuntu use the following commands one after another:

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

Voila! That should solve your problem. Hit the comment section for questions, suggestions and thanks :P