Translations:VirtualBox/10/en

Get extensionpack from VirtualBox

Same rule apply - match your VirtualBox version - usually the latest version applies.

Downloads – Oracle VM VirtualBox

If the latest version do not match yours - you can find earlier versions using this page

Download Old Builds - Oracle VM Virtualbox

The extension .vbox-extpack is a registered mime extension so just open the file and VirtualBox will install the extension pack. Provide your password when asked.