I tried this Zopelab's tip: http://www.zopelabs.com/cookbook/1075841024 .. with the idea of allowing my clients to open simple tables within their Excel spreadsheets. Using IE (our primary target browser) tt works fine sometimes, but most of the time they get an error message from IE itself that tells it can't download the file, after having showed the dialog Open|Save|Cancel. No relevant error message appears in the event log neither in the site error log object. Curious thing is that in that dialog box ( Open|Save|Cancel ), sometimes the file type appears and sometimes it doesn't. When it doesn't, it means the problem is about to happen. So after digging a little with Shane's Tcpwatch I've noticed that the file would open only whether a basic authentication header was sent, in despite of the cookie information (that is always sent). This problem only happens in IE. Using Opera or Firefox won't show any problem. Also I'm using CookieCrumbler, so after I removed the "login" object at the root of my app, IE is no longuer showing problems. Has anyone had this same experience and eventually come up with a workaround that still uses cookies authentication? Thanks in advance, Ausum