Virtualbox NS ERROR FAILURE "namespace error failure"

---

sudo pacman -Syyu

sudo /sbin/rcvboxdrv setup

---

pacman -Qqs virtualbox

sudo pacman -Syu
sudo pacman -S virtualbox-host-modules-arch

or install dkms

sudo pacman -Syu
sudo pacman -S linux-headers --needed
yes | sudo pacman -S virtualbox-host-dkms

sudo modprobe vboxdrv
sudo /sbin/rcvboxdrv setup

reboot 

or 

AUR install  virtualbox-bin