Ubuntu – Why do Guest Additions need kernel headers in VirtualBox 4.04.

You will need to install the kernel modules (headers) package that match the kernel version you are running the Ubuntu virtual machine with.

Type the following command in the terminal:

uname -a

This will give you line like this:

Linux dirk-Studio-1558 2.6.38-9-generic #43-Ubuntu SMP Thu Apr 28 15:23:06 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux

The first word is the type of system, the second is the name of your machine and the third one is the one you are looking for. It gives the kernel version.

So you need to install the linux-headers-{my kernel version here} package from Synaptic org using apt-get. In my case it would be

sudo apt-get install linux-headers-2.6.38-9-generic

or directly in one generic command:

sudo apt-cache search linux-headers-`uname -r`

Hope that helps!

edit:

Ok, if that is setup correctly you can try to install the packages listed here Check post #12

To get a VirtualBox ubuntu server guest to correctly accept a guest-additions install you will need to have a minimal xorg package install:

sudo apt-get install xserver-xorg xserver-xorg-core

By doing this, you will have the shared-folder support.

As you have found, the guest additions is one very large script - "VBoxLinuxAdditions.run"

You may be able to unpick this file - I wouldnt recommend it, because as newer versions of virtualbox is released, the version of guest-additions is usually bumped as well.

In addition, I would recommend (if you haven't already), install dkms. When newer ubuntu kernels are updated, the guest-additions kernel modules will be automatically compiled. Without dkms you will lose your shared-folder support when a kernel update is made.

source