When working with VirtualBox, sometimes its useful to clone a OS by just duplicate the *.vdi hard disk file and create a new OS with this hard drive. When you just copy and paste the .vdi file you’ll get an error because the uuids of the partions on the already in use by VirtualBox. The correct way to do this is:

on Windows:

%VIRTUAL_BOX_DIR%/VBoxManage.exe clonevdi ORIGINAL_FILE CLONE