Removing Virtualbox-5.1 in a stuck state
I had the same problem, but just a little bit differently. I tried to reinstall virtualbox (switching from distro to official release) and it failed to uninstall, so I could not remove or install the new copy. I managed to fix the issue by creating an empty file:
/usr/lib/virtualbox/prerm-common.sh
Edit: Make the file executable with chmod +x /usr/lib/virtualbox/prerm-common.sh
Then running sudo apt-get remove virtualbox
I had the same problem. I solved it by killing all the VB processes.
get all the processes containing VB
ps -A | grep VB
then kill all processes with the command
sudo kill <pid>
replace <pid>
with the process IDs of the processes you got from above command.
then run
sudo apt-get remove virtualbox-* --purge