I think this messages shouldn't be shown when user has already installed the suggested packages: Starting with version 4.0.0, virtualbox has USB-1 support. For USB-2 support, PXE-boot ability and VRDP support please emerge app-emulation/virtualbox-extpack-oracle package. Starting with version 5.0.0, virtualbox no longer has the "additions" and the "extension" USE flag. For installation of the guest additions ISO image, please emerge app-emulation/virtualbox-additions and for the USB2, USB3, VRDP and PXE boot ROM modules, please emerge app-emulation/virtualbox-extpack-oracle Thanks