Well, my PCLinuxOS installation is not fully updated. It is a PCLinuxOS 2007 installation. Short story, when I decided to use PCLinuxOS as my main OS two years ago, I made the decision to do selective updates only. So, I have been updating packages that are important for my daily work using Synaptic. The reason is that back then I heard horror stories about people who wrecked their working Linux installation after doing full updates/upgrades. Most of the Linux systems affected were other distributions and not PCLinuxOS. So, since I didn't see anything wrong with my installation and I had set everything up the way I wanted, I didn't want to do any full update and risked wrecking my working PCLinuxOS installation.
I found out much later that the rolling updates that PCLinuxOS has work well. But, I thought it was too late to do a full update since I had been doing selective updates for quite some time. So, when I decide to reinstall PCLinuxOS with the latest version, I will do the full update routine. For now, I just have to live with my current working PCLinuxOS installation.
Back to VirtualBox, yes I rebooted my laptop after I installed VirtualBox. Since the problem may be related to my not fully updated PCLinuxOS, what would happen if I decide to fully update it now? Would the full update wreck my Linux installation? I mean I don't want to reinstall everything since I had set up everything the way I wanted. Also, if it is possible, is there any workaround to start VirtualBox without doing the full update?