found this on google
What is the Vbox client or RTAcgi.exe or Installer.exe and why do I need it?
The Vbox client is the helper application that you will download with your first purchase of downloadable software. This application assists in downloading and decrypting your final product. This first time download is about 744 kilobytes in size.
perhaps you stopped the download too quickly.
you will now have to wait until tuesday to speak to the company, if you get no satisfaction the do not delay, Cancel the payment.
then phone them again, tell them what you have done (as in cancelled the payment) and also say if they want your bussiness now and in the future, then they had better think about improving thier customer relations.
also found this,
if you get an error message when you double click the downloaded file, is it this
Error "200, 2" - error when launching Installer.exe or rtacgi.exe from the desktop
if so take a look here
this seems to be for roxio's stuff but may be of help.