It looks like you downloaded an older version of the sand box and possibly the version for the incorrect virtualization program. The current version of the Sandbox does not have the word ‘Bombardier’ in its name. Also, you say that you are using virtual box but it looks like it’s trying to load a vmware file. Try downloading again making sure to download the version for Virtual Box. Also note that you do not need to extract the file once downloaded, simply import the appliance by going to the file->import appliance menu item and point it at the file you just downloaded.