remove virtualbox from ubuntu

#Uninstall VirtualBox first.

sudo apt-get remove --purge virtualbox 
#Run these commands to delete all virtual machines and settings and Virtual Hard Drives:

sudo rm ~/"VirtualBox VMs" -Rf
sudo rm ~/.config/VirtualBox/ -Rf
#If you want to install it again. Run this command:

sudo apt-get install virtualbox
#Additionally, check:

sudo ps aux | grep -i "vbox"
#Kill any "ghost" processes you may think are relevant.

sudo pkill VBox*