Virtio paravirtualised NIC drivers for Server 2008 / Win 7 on virtualbox

On your Virtualbox host; download the ISO of generic windows paravirtualised drivers from here:

http://alt.fedoraproject.org/pub/alt/virtio-win/latest/images/bin/

Shut down your Windows VM and set your its Adapter Type to “virtio-net”.

Boot the Windows Vm and mount the downloaded driver ISO as a virtual CD drive.

Log on to the VM and check you can browse to the virtual CD’s \Win 7\[x86|amd64]\ folder; use devmgmt.msc to install the new drivers on the paravirtualised NIC hardware (“Trust software from Redhat”).

You shouldn’t need to to reboot.