Installing VBox Extensions Via Command Line Interface
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VBoxManage extpack
The "extpack" command allows you to add or remove VirtualBox extension packs, as described in the section called “Installing VirtualBox and extension packs”.
To add a new extension pack, use VBoxManage extpack install <tarball>.
To remove a previously installed extension pack, use VBoxManage extpack uninstall <name>. You can use VBoxManage list extpacks to show the names of the extension packs which are currently installed; please see the section called “VBoxManage list” also. The optional --force parameter can be used to override the refusal of an extension pack to be uninstalled.
The VBoxManage extpack cleanup command can be used to remove temporary files and directories that may have been left behind if a previous install or uninstall command failed.
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