Topic: Install Guest additions and run fullscreen mode on VirtualBox Guest OS | Linux

[sam]

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Installing just VirtualBox , sometimes, does not resolves some of the problems. For example, seamless movement between host OS and guest will not work without installing Guest Additions.USB devices may not work without installing GuestAdditions, fullscreen mode not available. GuestAdditions are installed in the Guest OS where as VirtualBox is installed on the host.

http://www.unixmen.com/linux-tutorials/721-install-guest-additions-and-run-fullscreen-mode-on-virtualbox-linux-ubuntu-fedora