Vm's Settings > General Section > Advanced Tab > Enable PAE/NX PAE support on the virtual processor is available in VirtualBox, but must be enabled on a per processor basis. The server release requires the PAE extension to be available on the virtual processor presented by VirtualBox to the guest OS. There is a known issue with VirtualBox and the Ubuntu 8.04 and later Server releases. See VirtualBox/Previous for information on detailed instructions for older versions of Ubuntu and Virtualbox. Instructions are compiled from information from: If a newer version has since been released, please update the package name in the command to reflect that. The latest Virtualbox version at the time of writing was 5.0.

To install Virtualbox from the Oracle repository, copy paste this command into a terminal: sudo sh -c 'echo 'deb '$(lsb_release -cs)' contrib non-free' > /etc/apt//virtualbox.list' & wget -q -O- | sudo apt-key add - & sudo apt-get update & sudo apt-get install virtualbox-5.0 Installing VirtualBox from Ubuntu repositories is easiest. There are separate gratis closed-source extension packs with a few extra features, such as USB 2.0 support. There are two versions of VirtualBox available: one packaged by Ubuntu and one by Oracle.

Oracle vm virtualbox extension pack 5.0