Linux Software Updater – Clearsign file error

Recently I encountered problem with my Software Updater in Linux Mint Cinnamon. The Software Updater GUI in Linux Mint makes it a lot easier to see and manage your updates, just like Windows Update does for Windows.

I happened notice out the corner of my eye when shutting down a little red exclamation mark on my Software Updater system tray icon. Panicked I booted up my machine again to investigate and clicked on it to analyse the problem. I encountered a message

Clearsigned file '' contains unsigned lines.
The package lists or status file could not be parsed or opened.

I have deliberately removed the exact file from the above as it could be different from distro to distro and mirror to mirror

This is usually a sign of corruption of data downloaded from your mirror which gives you the list of available updates. Often you can simply overcome this by switching mirrors temporarily. If that doesn’t work well…

It’s really simple to fix with the below command

sudo rm -r /var/lib/apt/lists/*
sudo apt update

This will clear the list downloaded and when you restart the Software Updater it will download the list again and all should be well.