Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I am running an Ubuntu Server (12.0.4-beta2; kernel 3.2.0) in VirtualBox (host is Win7) and I want to use shared folders. I've followed the manual to set up vbox guest additions but this error occurs with every startup:

Starting the VirtualBox Guest Additions!
(modprobe vboxguest failed)
Starting VirtualBox Guest Addition service VirtualBox Additions module not loaded!

When I try it myself:

$ modprobe vboxguest
FATAL: Module vboxguest not found.

Did I do something wrong, what do I need to fix it? Thanks for help.

share|improve this question
Put some kmesg on pastebin and post the link? – Apr 15 '12 at 1:25
Thanks. How do I do this? cat /proc/kmsg doesn't write anything. – A123321 Apr 15 '12 at 9:56
Sorry, it should be sudo dmesg > file.log – Apr 15 '12 at 9:58
Here it is – A123321 Apr 16 '12 at 10:44
up vote 3 down vote accepted

I had this problem today, and solved it by installing the kernel-headers

yum install dkms binutils gcc make patch libgomp glibc-headers glibc-devel kernel-headers 


yum install kernel-devel


yum install kernel-pae-devel

Then re-run

share|improve this answer
For people coming across this in the future, this did the trick perfectly for me on a fresh install of CentOS 6.2 – AndyPerfect May 16 '12 at 23:25
This works because compiles the VirtualBox kernel modules, but doesn't quite mention this when it fails. – Piskvor Feb 27 '14 at 16:10

I discovered here that the standard guest additions install includes a built-in setup function, so there's no need to reinstall:

/etc/init.d/vboxadd setup

This gave me the error about missing kernel sources, so as brendan's answer, yum install kernel-devel, and then that setup command works, and everything seems to be back to normal again!

share|improve this answer
This worked for me. – Parthian Shot Feb 22 at 16:07

I had a similar problem today, but it turns out the vagrant-vbguest plugin was not installed. So, in the folder with my Vagrantfile:

vagrant plugin install vagrant-vbguest

That solved it for me.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.