ON HOST-SYSTEM (WINDOWS)
========================
- Create shared folder, e.g.
  <D:\Virtual Box\sharedfolder>
- Create a "check file" within this folder, e.g.
  <checkfile.txt>


IN VB APPLICATION
=================
Machine
-> Settings
   -> Shared Folders
      -> Add Folder (+ Icon on the right)
         -> Select the Folder above and give it a Folder Name, e.g. <sharedfolder>


ON GUEST-SYSTEM (LINUX)
=======================
- login as root user
- add the sharedfolder to the file system table (vi /etc/fstab, add the next line)
  sharedfolder    /sharedfolder       vboxsf defaults   0 0
- reboot
- change to shared folder
  cd /sharedfolder
- checkfile should be there and can be removed