How To Install VirtualBox Under Ubuntu Gutsy (7.10)

Source: virtualbox wiki

First of all, forget about the standard Ubuntu virtualbox distribution. It didn't work for me.

Instead, use the virtualbox.org repository. Add the following line to your /etc/apt/sources.list (directly, or through the Synaptic Package Manager):

deb http://www.virtualbox.org/debian gutsy non-free

Download and add (register) the repository key:

wget -q http://www.virtualbox.org/debian/innotek.asc -O- | sudo apt-key add - (or skip this step if you don't mind the one-time non-consequential error message)

Use the Synaptic Package Manager (or any other means) to install virtualbox. Afterwards, add yourself (and any other users who may want to use virtualbox) to the virtualbox usergroup:

Administration > Users and Groups > Manage Groups > vboxusers > Properties (then add yourself there)

Now login again for the usergroup changes to take effect! If all is set, go to Applications > System Tools > innotek VirtualBox to start virtualbox. Keep your Windows installation CDs at hand!

You can use http://10.0.2.2 to access the localhost of the guest system. You can also map this ip address to a local host name, using C:\windows\system32\drivers\etc\hosts:

10.0.2.2   compass

If you've used the same name for a local host on your guest system, you can now use http://compass in both MS IE in the VM, and in your linux system!