Problem pushing Excel file to browser

I am trying to get an Excel version of a report pushed to the user's browser.  In the load event of my page I grab the report object out of the seesion, run the export to excel function on it (this is an Active Reports feature), then spit it out to the browser. This works fine on my development machine. It does not, however, work so well when I publish the code to my Test server or Production server. What ends up happening is that the page appears breifly and then goes away when you should be seeing the open / save file dialog. I read in a post somewhere that there is a problem doing what I'm trying to do in the load event if the site is running https, which both my test and production servers are. They are both running IIS version 6, the ASP.net version is set to 2.0.50727. As a work around I have placed a button on the page and moved the code to the button's click event handler and evertying works. This is an unacceptable work aro ...