For those people who use Mageia 2 and like to test other OSs or need to keep another OS for work purposes, installing Virtualbox from the Mageia repositories might lead them to a disappointment. The distro seems to only support Virtualbox OSE (as it is the only package in the repos), which does not allow one to enable USB support. Therefore, you end up with a Virtual Machine that cannot read your flash drive.
To solve this pesky problem, you must understand that the situation springs from having installed a Virtualbox version that does not do what you need or want. You must, then uninstall it and grab the Virtualbox PUEL version package from the Oracle site here.
For Mageia 2, you need to use version 4.1.24 (it is the version that matches the kernel in the Mageia 2 repos), so scroll and clic on the link "older builds".
Download the Mandriva 2011 rpm package (VirtualBox-4.1-4.1.24_82872_mdv2011.0-1.i586.rpm) and do not forget to download the extension pack as well.
Then, click on it to install it. You are going to get a warning about an invalid signature; just ignore it and proceed. If there are some dependencies needed, the package manager will get them for you. Make sure you also install the dkms-virtualbox package from the repos.
Once the dkms package is installed, you can fire up Virtualbox and create a virtual machine. You will notice that USB support is still disabled. To change this situation, you must do this:
1. Open MCC and go to System and Manage Users. Find your user and add it to the vboxsr and vboxusers groups.
2. Install the extension pack you downloaded. To do this, log out and back in and click on the file. It will be installed automatically for you after you accept the license for public use evaluation.
Then, after you start your virtual machine, insert the USB stick and check its corresponding box in devices-> USB (You might need to mount the USB on the host system before it is displayed in the Virtual machine).
This performs the trick.