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  <title>Alternative Firmware (UEFI)</title>
  <body>
    <p><ph conkeyref="vbox-conkeyref-phrases/product-name"/> includes support for the Unified Extensible Firmware Interface (UEFI), which is an industry standard intended to replace the legacy BIOS as the primary interface for bootstrapping computers and certain system services later.</p>
    <p>By default, <ph conkeyref="vbox-conkeyref-phrases/product-name"/> uses the BIOS firmware for virtual machines. To use UEFI for a given virtual machine, you can enable EFI in the machine's <b outputclass="bold">Settings</b>. See <xref href="settings-motherboard.dita#settings-motherboard"/>. Alternatively, use the <userinput>VBoxManage</userinput> command line interface as follows:</p>
    <pre xml:space="preserve">VBoxManage modifyvm "VM name" --firmware efi</pre>
    <p>To switch back to using the BIOS:</p>
    <pre xml:space="preserve">VBoxManage modifyvm "VM name" --firmware bios</pre>
    <p>Most modern macOS and Windows releases require UEFI. All Arm VMs require UEFI.</p>
    <p>Another possible use of UEFI in <ph conkeyref="vbox-conkeyref-phrases/product-name"/> is development and testing of UEFI applications, without booting any OS.</p>
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