You are not a member of the "vboxusers" group. Please add yourself to this
group before starting VirtualBox
/dev/vboxdrv not writable for some reason. If you recently added the current
user to the vboxusers group then you have to logout and re-login to take the
WARNING: The compilation of the vboxdrv.ko kernel module failed during the
installation for some reason. Starting a VM will not be possible.
Please consult the User Manual for build instructions.