Network Programming in .NET

By default IIS7 will not serve files with unknown MIME types, one of these could be the .torrent file type, which simply returns a 404 error.

From a command prompt, run %windir%\system32\inetsrv\appcmd set config /section:staticContent /+”[fileExtension=’.torrent’,mimeType=’application/x-bittorrent’]”

Then IISReset

(I’m not 100% sure if IISReset is required, but it worked for me).