I have been using Free Oracle Virtual Box since quite a while and I take back up of the hard disk file (Lucid Lynx.vdi) regularly so that I don’t loose any installation and configuration I have done in Ubuntu in case of any OS crash.

Host OS :- Windows XP

Guest OS :- Ubuntu 10.04

1.Install the Guest Additions. (Make sure from command line that its successful )

2.Share a windows folder at Settings –> “Shared folders ”  -> Add machine folder eg.  “dev”  as name and  path D:\dev

3.Boot the guest OS and go to terminal

4 make folder to be the destination of the mount mkdir ~host

5. sudo mount -t vboxsf dev ~/host

6.For mounting automatically everytime you boot add the above line at /etc/rc.local

Now the folder ~host gives me access to all the contents of D:\dev directory in windows drive.

Courtesy http://forums.virtualbox.org/viewtopic.php?t=15868

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