I've installed Ubuntu 11.10 on a new Lenovo Thinkpad 420s and I'm trying to get some VirtualBox VMs up and running (using Vagrant). Everything works fine until I try to add host-only networking. This is the failure I get in the terminal:

I set logging to debug and tried again. Here's a paste of the relevant portion of the log.

When I try to add host-only networks with the VirtualBox gui (File->Preferences->Networking->Add host-only networking), I get the following error message:

This error is occurring with three different virtual boxes, all Ubuntu 11.10 64bit guests, one of which I've run without issue on a Windows host and an OSX host.

Here is the Vagrantfile for the box I've successfully run on Windows and OSX:

Vagrant::Config.run do |config|
  config.vm.box = "ubuntu-11.10"
  config.vm.box_url = "http://timhuegdon.com/vagrant-boxes/ubuntu-11.10.box"
  config.vm.network :hostonly, "192.168.33.10"
  config.vm.customize ["modifyvm", :id, "--memory", "512"]
  config.vm.customize ["modifyvm", :id, "--natnet1", "10.0.28.0/24"]
  config.vm.forward_port 80, 4567
end

I've tried two other boxes as well, one of which I built last night with veewee, all of which are getting the exact same error.

I've used rvm to install ruby 1.9.3-p125 [ x86_64 ], and I've got Vagrant running in its own gemset.

I've Googled quite a lot and haven't been able to find any resolution. Suggestions?