The question at hand is:How to completely remove (purge) unused (removed via GUI) kernel packages in Linux Mint 18.x after man removes these kernels via Mint Update Manager -> Linux Kernels window?As you can see below, there is only one kernel installed, I have removed all others:Since they were removed, I presumed they were purged completely, but I was wrong. Once I did:dpkg --list | grep linux-imageThere was more like 30 packages with rc prefix.
How to completely remove unused kernel packages in Linux Mint?
linux mint;linux kernel
The rc prefix - these two letters signify the status of the packages as follows:r : the package was marked for removalc : the configuration files are present in the systemFirst we need to get the list of the packages, that were removed, while leaving the configuration behind:dpkg --list | grep ^rc  linux-image | cut --delimiter   --fields 3Once we have the list, we can manually purge these kernel packages, e.g.:sudo apt-get purge linux-image-4.10.0-20-generic linux-image-extra-4.10.0-20-genericNotice, we are actually always removing two packages:linux-image-*linux-image-extra-*One problem you will possibly encounter is a warning that the kernel library directory wasn't removed because it's not empty. I decided that I will leave it as it is, because I would have to google another hour for an explanation whether or not I can just:sudo rm -rf /lib/modules/4.10.0-20-generic/