This is the scenario that you run Windows as your host operating system and Ubuntu live cd in a VirtualBox, and that you want to access a specific Windows folder from Ubuntu.
Preparation setting
1. After create new machine on Vbox, go to Setting menu
2. Choose the Storage menu, on the IDE Controller create new 2 virtual CD/DVD device
3. In the first virtual cd, mount the ubuntu.iso from hardisk
4. In the second virtual cd, mount the VBoxGuestAdditions.iso
5. In the System menu, setting boot order for CD/DVD-ROM only
Create share folder on the Vbox
1. Create new folder for share on wind XP, ex: C:\OZI
2. Choose the Share Folders menu in the Devices menu
3. Navigate to C:\OZI
Mount share folder into ubuntu
1. Run the VBox, chose try ubuntu without any change on your computer
2. Create new folder on ubuntu to mount OZI folder, ex /home/ubuntu/Desktop/OZI_XP
3. Try to access /media/VBOXADDITIONS_3.1.4_57640/VBoxLinuxAdditions-x86.run using super user on the shell by type : sudo /media/VBOXADDITIONS_3.1.4_57640/VBoxLinuxAdditions-x86.run
4. Mount the OZI to OZI_XP by type : sudo mount -t vboxsf OZI /home/ubuntu/Desktop/OZI_XP
Ok, thats all, when you create new file in the /home/ubuntu/Desktop/OZI_XP it mean you create new file in the C:\OZI