The solution is to run '/etc/init.d/vboxdrv setup' and sometimes happens when upgrading VBox and the kernel modules don't get upgraded with it. Sometimes the above doesn't work until you reboot because sometimes other unknown processes (even the file manager possibly) may be locking the old module from being unloaded.
Failed to open a session for the virtual machine XP.
The virtual machine 'XP' has terminated unexpectedly during startup with exit code 1.
Kernel driver not installed (rc=-1908)
The VirtualBox Linux kernel driver (vboxdrv) is either not loaded or there is a permission problem with /dev/vboxdrv. Please reinstall the kernel module by executing
as root. If it is available in your distribution, you should install the DKMS package first. This package keeps track of Linux kernel changes and recompiles the vboxdrv kernel module if necessary.
WARNING: Deprecated config file /etc/modprobe.conf, all config files belong into /etc/modprobe.d/.
WARNING: All config files need .conf: /etc/modprobe.d/blacklist, it will be ignored in a future release.
Stopping VirtualBox kernel modules ...done.
Uninstalling old VirtualBox DKMS kernel modules ...done.
Trying to register the VirtualBox kernel modules using DKMS ...done.
Starting VirtualBox kernel modules ...done.
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