Anthony, you're my new hero :-)  I eliminated all the HTTP headers I set 
related to stopping browsers from caching my dynamically generated XML and 
things worked in both IE 6 and IE 7 with HTTPS.  Unfortunately, the XML got 
cached (mmm, even with an HTTPS connection?) and this therefore broke my 
application.  So, as you originally suggested, I got rid of just no-store but 
this caused things to revert back to the old problem.  So, it would seem that 
setting the no-cache directive is also a problem here.  I finally ended up 
setting just the "Expires" header to zero and this didn't cause problems with 
IE, plus it prevented the XML from being cached in both IE and Firefox (I 
guess I was just being too fancy with all my "don't cache this" settings :-)

I am happy with the world again.  Thanks to you and thanks to Joe as well.

Cheers,
-Steve

"Anthony Jones" wrote:

> 
> Can you try it without the no-store cache control value.  Sometimes this
> header causes WinInet (the component of windows being used to fetch the
> document) some trouble.
> 
> > Thanks,
> > -Steve
> >