Frankly, I never managed to get up and flawlessly running VirtualBox version which is bundled with Ubuntu. VirtualBox from https://www.virtualbox.org/wiki/Downloads worked perfectly though.
Well, sometimes, generally after major kernel updates, VirtualBox complains that it has no appropriate module. I.e. I see that it refuses to start and I run it from command line. That is the trick: VB not only throws an error message to console, but prompts a command which I have to issue for recompilation of broken module, etc.