Virtual Box 4.x upgrade problem on Ubuntu 11.04 (Natty)

After upgrading to Ubuntu 11.04 from 10.10, you might encounter errors while using Virtual Box.

Trying to compile Virtual Box throws the following error:

Error! Your kernel headers for kernel 2.6.38-10-generic-pae cannot be found at 
/lib/modules/2.6.38-10-generic-pae/build or /lib/modules/2.6.38-10-generic-pae/source.

 

You have to run the following command:

sudo apt-get install linux-headers-$(uname -r)

 

followed by:

sudo /etc/init.d/vboxdrv setup

 

This will rebuild Virtual Box from its sources.

Mounting USB devices into Oracle VirtualBox in Ubuntu

Apparently, you need to add your logged-in user into vboxusers group.

Check this link: http://www.howtogeek.com/howto/31726/mount-usb-devices-in-virtualbox-with-ubuntu/