I get this error after upgrade

Open terminal and execute these commands:

sudo apt-get autoremove
sudo apt-get --purge remove && sudo apt-get autoclean
sudo apt-get -f install
sudo dpkg-reconfigure -a

_{Last command would take some time depends upon packages installed in your system. So please be patient. If you don't have any broken/residual packages it would execute silently without any message.}

sudo apt-get update
sudo apt-get upgrade && sudo apt-get dist-upgrade
sudo dpkg-reconfigure -a
sudo dpkg --configure -a
sudo update-initramfs -u

Then restart your system.

My one-liner to remove old kernels (this also frees up disk space):

dpkg --list | grep linux-image | awk '{ print $2 }' | sort -V | sed -n '/'`uname -r`'/q;p' | xargs sudo apt-get -y purge

Explanation (remember, | uses the output of the previous command as the input to the next)

• dpkg --list lists all installed packages
• grep linux-image looks for the installed linux images
• awk '{ print $2 }' just outputs the 2nd column (which is the package name)
• sort -V puts the items in order by version number
• sed -n '/'`uname -r`'/q;p' prints the lines before the current kernel
• xargs sudo apt-get -y purge purges the found kernels

Unwinding the sed invocation:

• -n tells sed to be quiet
• `uname -r` outputs the current installed kernel release - we include it in backticks so that the output is includes as part of the command (you might also see this as $(uname -r)
• /something/q says stop when you match 'something' (in this case, something is output of uname -r) - the / surround a regular expression
• p is print
• the ; is the command separtor, so /something/q;p says quit when you match something, else print

altogether, sed -n '/'`uname -r`'/q;p' is print the lines until it matches with the current kernel name.

If you're paranoid (like me), you can make the last part xargs echo sudo apt-get -y purge so that the command to purge the old kernels is printed, then you can check that nothing unexpected is included before you run it.

Modified version to remove headers:

dpkg --list | grep 'linux-image' | awk '{ print $2 }' | sort -V | sed -n '/'"$(uname -r | sed "s/\([0-9.-]*\)-\([^0-9]\+\)/\1/")"'/q;p' | xargs sudo apt-get -y purge
dpkg --list | grep 'linux-headers' | awk '{ print $2 }' | sort -V | sed -n '/'"$(uname -r | sed "s/\([0-9.-]*\)-\([^0-9]\+\)/\1/")"'/q;p' | xargs sudo apt-get -y purge

Note: the sed invocation is modified. "$(uname -r | sed "s/\([0-9.-]*\)-\([^0-9]\+\)/\1/")" extracts only the version (e.g. "3.2.0-44") , without "-generic" or similar from uname -r

All-in-one version to remove images and headers (combines the two versions above):

echo $(dpkg --list | grep linux-image | awk '{ print $2 }' | sort -V | sed -n '/'`uname -r`'/q;p') $(dpkg --list | grep linux-headers | awk '{ print $2 }' | sort -V | sed -n '/'"$(uname -r | sed "s/\([0-9.-]*\)-\([^0-9]\+\)/\1/")"'/q;p') | xargs sudo apt-get -y purge