includes experimental support for the Extensible Firmware Interface (EFI), which is an industry standard intended to replace the legacy BIOS as the primary interface for bootstrapping computers and certain system services later.

By default, uses the BIOS firmware for virtual machines. To use EFI for a given virtual machine, you can enable EFI in the machine's Settings window. See . Alternatively, use the VBoxManage command line interface as follows:

VBoxManage modifyvm "VM name" --firmware efi

To switch back to using the BIOS:

VBoxManage modifyvm "VM name" --firmware bios

One notable user of EFI is Apple Mac OS X. More recent Linux versions and Windows releases, starting with Vista, also offer special versions that can be booted using EFI.

Another possible use of EFI in is development and testing of EFI applications, without booting any OS.

Note that the EFI support is experimental and will be enhanced as EFI matures and becomes more widespread. Mac OS X, Linux, and newer Windows guests are known to work fine. Windows 7 guests are unable to boot with the EFI implementation.