Problem with downloading files from a ASP.NET site running SSL

I have an ASP.NET application in which "response.redirect" is used to redirect users to Excel spreadsheets, Word documents, PDFs, etc. When the user clicks the button to get to one of these documents, Excel or Word or Acrobat Reader is supposed to open and display the file. However, when we enable SSL on the site, the files do not open and we instead get a message box with "Microsoft Excel" (for example) in the title bar that says Excel could not open the URL. Then, it says Microsoft can't open the file or path because of some general errors. Internet Explorer then also provides it's own page indicating that the file could not be opened.

Without SSL, it works fine. Obviously, this is an SSL-related problem. But maybe some of you may have dealt with this before and know an easy way to remedy the problem.

Your help would be greatly appreciated!