Virtualbox

1. wget -q http://download.virtualbox.org/virtualbox/debian/oracle_vbox.asc -O- | sudo apt-key add -

2. sudo sh -c 'echo "deb http://download.virtualbox.org/virtualbox/debian trusty contrib" >> /etc/apt/sources.list.d/virtualbox.list'

3. sudo apt-get update

4. sudo apt-get install virtualbox-5.0

5. Oracle VM VirtualBox Extension Pack (https://www.virtualbox.org/wiki/Downloads)

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sudo apt-get install dkms
sudo apt-get install gnome-system-tools
Users and Groups > Manage Groups > vboxusers > Properties > OK.