CharleyO: it's not that 'Virtual Directory'
Tech: yeah, you're right
In Apache's (our webserver) terminology that means if the directory does not have any index file (index.html, index.htm, index.php or so), it by default tries to display the contents of a directory in human readable form with links and icons and such.
We've disabled such feature (because of multiple reasons), that's why you can point your browser to existing directory, but still get message about non-existing directory
It's possible to get the file from the directory, though.