When you want to copy/move from a shared folder (on Windows guests, for example) and it fails with absurd error messages (lots of text or an error about the target being read-only), you are probably running on Guest Additions that no longer match your VirtualBox version.
Fix: install the latest VirtualBox Guest Additions in your guest machine.
Note that you need to make sure you are using the correct ISO.
Posted by Arne Hartherz to makandra dev (2012-11-22 10:21)