Comment 9 for bug 253831

try doing /etc/init.d/vboxdrv restart, then running virtualbox. if that works read on:

if you have been doing an upgrade on intrepid for a while, you are stuck with some old settings that dont work (but have since been fixed on fresh installs)
if you remove and purge all the virtualbox stuff, and reinstall, all should be good from now on.

and of course, be sure to install virtualbox and virtualbox-ose-source packages

mark this bug as fix released if this fixes your problems