VirtualBox/Guest Additions/Windows

Here we install the Guest Additions^[1].

Go to the host operating system. At the top of the VM window, choose Devices >> "Insert Guest Additions CD image...". Then, VirtualBox simulates inserting a CD into the simulated optical drive of the VM.
If you need to eject this, you can either restart the VM or click on Devices >> optical drives >> eject.

If you didn't add a Windows shared folder into the "configuration" menu of the VirtualBox graphical interface^[2], you can do it in Command Prompt with: VBoxManage sharedfolder add "VMName" --name "SharedName" --hostpath "C:\Users\Public\Documents\SharedFolderPath".

Linux guest

The Guest Additions CD should be read from the guest OS like this^[3]:

sudo mount /dev/cdrom /media/cdrom
cd /media/cdrom
sudo ./VBoxLinuxAdditions.run

Then, just mount the Windows folder from Linux^[4]: mkdir ~/vboxshare sudo mount -t vboxsf SharedName ~/vboxshare

That's it, you can browse your Windows files: ls ~/vboxshare

References

[1] VirtualBox manual, "Guest Additions"

[2] ttp://www.htpcbeginner.com/mount-virtualbox-shared-folder-on-windows/

[3] ttp://superuser.com/questions/950431/how-to-install-virtual-box-guest-additions-on-debian

[4] ttps://help.ubuntu.com/community/VirtualBox/SharedFolders

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