Forbidden: 

<!-- This file is called installer (rather than downloader) so that Windows Vista will
'elevate' the downloaded file (else the unpacker says 'can't run setup').  Note that Vista
(wrongly, in my opinion) uses the name of the .aspx file, rather than the attachment, to
make this decision -->

<!-- The file to be downloaded is output from the PageLoad handler in downloader.aspx.cs -->