This is one way to set up a shared folder in VirtualBox VM.
- mkdir Shared in /home/username on host
- Add Shared /home/username in VBox Settings>Shared Folders
- mkdir Shared in /home/username on guest
- As root (or super user) add
Shared /home/username/Shared vboxsf defaults 0 0to
Note: Change username to your unique username. username has to be the same on host and guest for this to work. There are other ways to do this as far as how one sets up the folder.